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Write each mixed expression as a rational expression. 1. SOLUTION: 2. SOLUTION: 3. SOLUTION: eSolutions Manual - Powered by Cognero Page 1 11 - 7 Mixed Expressions and Complex Fractions

Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

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Page 1: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 1

11-7 Mixed Expressions and Complex Fractions

Page 2: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 2

11-7 Mixed Expressions and Complex Fractions

Page 3: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 3

11-7 Mixed Expressions and Complex Fractions

Page 4: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 4

11-7 Mixed Expressions and Complex Fractions

Page 5: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 5

11-7 Mixed Expressions and Complex Fractions

Page 6: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 6

11-7 Mixed Expressions and Complex Fractions

Page 7: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 7

11-7 Mixed Expressions and Complex Fractions

Page 8: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 8

11-7 Mixed Expressions and Complex Fractions

Page 9: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 9

11-7 Mixed Expressions and Complex Fractions

Page 10: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 10

11-7 Mixed Expressions and Complex Fractions

Page 11: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 11

11-7 Mixed Expressions and Complex Fractions

Page 12: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 12

11-7 Mixed Expressions and Complex Fractions

Page 13: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 13

11-7 Mixed Expressions and Complex Fractions

Page 14: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 14

11-7 Mixed Expressions and Complex Fractions

Page 15: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 15

11-7 Mixed Expressions and Complex Fractions

Page 16: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 16

11-7 Mixed Expressions and Complex Fractions

Page 17: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 17

11-7 Mixed Expressions and Complex Fractions

Page 18: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 18

11-7 Mixed Expressions and Complex Fractions

Page 19: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 19

11-7 Mixed Expressions and Complex Fractions

Page 20: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 20

11-7 Mixed Expressions and Complex Fractions

Page 21: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 21

11-7 Mixed Expressions and Complex Fractions

Page 22: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 22

11-7 Mixed Expressions and Complex Fractions

Page 23: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 23

11-7 Mixed Expressions and Complex Fractions

Page 24: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 24

11-7 Mixed Expressions and Complex Fractions

Page 25: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 25

11-7 Mixed Expressions and Complex Fractions

Page 26: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 26

11-7 Mixed Expressions and Complex Fractions

Page 27: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 27

11-7 Mixed Expressions and Complex Fractions

Page 28: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 28

11-7 Mixed Expressions and Complex Fractions

Page 29: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 29

11-7 Mixed Expressions and Complex Fractions

Page 30: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 30

11-7 Mixed Expressions and Complex Fractions

Page 31: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 31

11-7 Mixed Expressions and Complex Fractions

Page 32: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 32

11-7 Mixed Expressions and Complex Fractions

Page 33: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 33

11-7 Mixed Expressions and Complex Fractions

Page 34: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 34

11-7 Mixed Expressions and Complex Fractions

Page 35: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 35

11-7 Mixed Expressions and Complex Fractions

Page 36: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 36

11-7 Mixed Expressions and Complex Fractions

Page 37: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 37

11-7 Mixed Expressions and Complex Fractions

Page 38: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 38

11-7 Mixed Expressions and Complex Fractions

Page 39: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 39

11-7 Mixed Expressions and Complex Fractions

Page 40: Write each mixed expression as a rational expression....Write each mixed expression as a rational expression. 62/87,21 62/87,21 62/87,21 62/87,21 52:,1* Rico rowed a canoe miles in

Write each mixed expression as a rational expression.

1. 

SOLUTION:  

2. 

SOLUTION:  

3. 

SOLUTION:  

4. 

SOLUTION:  

5. ROWING  Rico rowed a canoe miles in  hour.

a.  Write an expression to represent his speed in miles per hour. b.  Simplify the expression to find his average speed.

SOLUTION:  a. Use the formula d = r × t to write an expression for Rico's speed, r. 

  b. Simplify the complex fraction to find his average speed.

 

So, Rico's average speed is .

Simplify each expression.

6. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

7. 

SOLUTION:  To simplify complex fractions, rewrite as a division expression, then rewrite as a multiplication expression. 

8. 

SOLUTION:  

9. 

SOLUTION:  

10. 

SOLUTION:  

11. 

SOLUTION:  

12. 

SOLUTION:  

13. 

SOLUTION:  

Write each mixed expression as a rational expression.

14. 

SOLUTION:  

15. 

SOLUTION:  

16. 

SOLUTION:  

17. 

SOLUTION:  

18. 

SOLUTION:  

19. 

SOLUTION:  

20. 

SOLUTION:  

21. 

SOLUTION:  

22. 

SOLUTION:  

23. READING  Ebony reads pages of a book in 9 minutes. What is her average reading rate in pages per minute?

SOLUTION:  The number of pages Ebony reads equals the product of the rate she reads per minute and the time she reads in minutes, or N = r × t.  

 

Her average reading rate  is  page/minute.

24. HORSES  A thoroughbred can run  mile in about   minute. What is the horse’s speed in miles per hour?

SOLUTION:  

Use the formula d = rt  or   to represent the horse's speed in miles per minute and convert minutes to hours.

 

  The horse’s speed is 40 miles/hour.

Simplify each expression.

25. 

SOLUTION:  

26. 

SOLUTION:  

27. 

SOLUTION:  

28. 

SOLUTION:  

29. 

SOLUTION:  

30. 

SOLUTION:  

31. 

SOLUTION:  

32. 

SOLUTION:  

33. CCSS MODELING  The Centralville High School Cooking Club has pounds of flour with which to make

tortillas. There are cups of flour in a pound, and it takes about  cup of flour per tortilla. How many tortillas can 

they make?

SOLUTION:  First find out how many total cups of flour the Club has by multiplying the number of pounds of flour times the amount of cups in a pound.  

 

They have cups of flour. Each tortilla needs about  cup of flour. To find out how many tortilla they can make,

divide the total cups of flour by .

 

  So, they can make about 140 tortillas.

34. SCOOTER  The speed v of an object spinning in a circle equals the circumference of the circle divided by the time T it takes the object to complete one revolution. a.  Use the variables v, r (the radius of the circle), and T to write a formula describing the speed of a spinning object.

b.  A scooter has tires with a radius of inches. The tires make one revolution every  second. Find the speed in

miles per hour. Round to the nearest tenth.

SOLUTION:  

a. The circumference of a circle is 2πr. So, the velocity of an object is .

  b.

  The speed of the scooter is about 12.5 mi/hr.

35. SCIENCE  The density of an object equals , where m is the mass of the object and V is the volume. The

densities of four metals are shown in the table. Identify the metal of each ball described below. (Hint: The volume of

a sphere is   .)

 

  a.  A metal ball has a mass of 15.6 kilograms and a radius of 0.0748 meter. b.  A metal ball has a mass of 285.3 kilograms and a radius of 0.1819 meter.

Metal Density (kg/m3)

copper 8900 gold 19,300 iron 7800 lead 11,300

SOLUTION:  a.

 

 

The density is about 8900 kg/m3. Therefore, the metal ball is made of copper.

b.

 

The density is about 11,317 kg/m3. Therefore, the metal ball is made of lead.

36. SIRENS  As an ambulance approaches, the siren sounds different than if it were sitting still. If the ambulance is moving toward you at v miles per hour and blowing the siren at a frequency of f , then you hear the siren as if it were

blowing at a frequency h. This can be described by the equation , where s is the speed of sound,

approximately 760 miles per hour. a.  Simplify the complex fraction in the formula. b.  Suppose a siren blows at 45 cycles per minute and is moving toward you at 65 miles per hour. Find the frequencyof the siren as you hear it.

SOLUTION:  a.

 

b. Substitute 65 for v, and 45 for f in the equation .

 

  The frequency of the siren as you hear it is 49.21 cycles/min.

Simplify each expression.

37. 

SOLUTION:  

38. 

SOLUTION:  

39. 

SOLUTION:  

40. 

SOLUTION:  

41. 

SOLUTION:  

42. 

SOLUTION:  

43. REASONING  Describe the first step to simplify the expression shown.

SOLUTION:  Find the lowest common denominator for the fractions in the numerator. Then subtract and simplify. 

44. REASONING  Is   sometimes, always, or never equal to 0? Explain.

SOLUTION:  

  This expression is always equal to 0.

45. CCSS PERSEVERANCE  Simplify the rational expression shown.

SOLUTION:  

46. OPEN ENDED Write a complex fraction that, when simplified, results in .

SOLUTION:  

Find two fractions that have the same denominators and when you divide the numerators, you get

 

Consider the fraction . It simplifies to .

 

47. WRITING IN MATH  Explain how complex fractions can be used to solve a problem involving distance, rate, and time. Give an example.

SOLUTION:  

Sample answer: Time equals distance divided by rate or . When the distance or the rate is given as a fraction or

mixed number, the expression  becomes a complex fraction. Example: Someone walks   mile in 10 minutes;

the time in miles per minute is , which simplifies to  mi/min.

 

48. A number is between 44 squared and 45 squared. 5 squared is one of its factors, and it is a multiple of 13. Find the number. A  1950 B  2000 C  2025 D  1975

SOLUTION:  The value of 44 squared is 1936. The value of 45 squared is 2025. Therefore, the answer cannot be C.  

 

The only number that has 52 as one of its factors and is a multiple of 13 is 1950. So, the correct choice is A.

Number Prime Factorization

Exponential Form

1950 2 • 3 • 5 • 5 • 13 2 • 3 • 52 • 13

2000 2 • 2 • 2 • 2 • 5 • 5 •5

24 • 5

3

1975  5 •5•79 52 • 79

49. SHORT RESPONSE  Bernard is reading a 445-page book. He has already read 157 pages. If he reads 24 pages aday, how long will it take him to finish the book?

SOLUTION:  Bernard still needs to read 445 – 157 or 288 pages. He will read 24 pages a day. It will take him 288 ÷ 24 or 12 daysto finish the book.

50. GEOMETRY  Angela wanted a round rug to fit her room that is 16 feet wide. The rug should just meet the edges. What is the area of the rug rounded to the nearest tenth? F  100.5 ft

G  804.2 ft2

H  50.3 ft

J  201.1 ft2

SOLUTION:  

The area of a circle is A = πr2. If the rug just meets the edge of the room, then the diameter is 16 feet, so the radius

is 16 ÷ 2 or 8 feet.  

  The area of the rug is about 201.1 square feet. So the correct choice is J.

51. Simplify .

A  

B  

C  

D  

SOLUTION:  

  The correct choice is B.

Find each sum or difference.

52. 

SOLUTION:  

53. 

SOLUTION:  

54. 

SOLUTION:  

55. 

SOLUTION:  

Find the LCD of 5m and 15m3. The LCD is 15m

3.

 

56. 

SOLUTION:  Find the LCD of 3g and 4h. The LCD is 12gh. 

57. 

SOLUTION:  Find the LCD of (b + 3) and (b – 2). The LCD is (b + 3)(b – 2). 

Find each quotient. Use long division.

58. (x2 − 2x − 30) ÷ (x + 7)

SOLUTION:  

The quotient is .

59. (a2 + 4a − 22) ÷ (a − 3)

SOLUTION:  

The quotient is .

60. (3q2 + 20q + 11) ÷ (q + 6)

SOLUTION:  

The quotient is .

61. (3y3 + 8y

2 + y − 7) ÷ (y + 2)

SOLUTION:  

The quotient is .

62. (6t3 − 9t

2 + 6) ÷ (2t − 3)

SOLUTION:  

The quotient is .

63. (9h3 + 5h − 8) ÷ (3h − 2)

SOLUTION:  

The quotient is .

64. GEOMETRY A rectangle has a base of 8 meters and a height of 14 meters. What is the length of the diagonal?

SOLUTION:  Use the Pythagorean theorem. 

Graph each function. Determine the domain and range.

65. 

SOLUTION:  Use perfect squares for the x-values of the table.

   

The domain is {x|x ≥ 0}, and the range is {y |y  ≥ 0}.

x y

0 0

1 2

4 4

9 6

66. 

SOLUTION:  Use perfect squares for the x-values of the table.  

 

  The domain is {x|x ≥ 0}, and the range is {y |y  ≤ 0}.

x y

0 0

1 –3

4  –6

9 –9

67. 

SOLUTION:  Use perfect squares for x-values of the table.  

 

The domain is {x| x ≥ 0}, and the range is {y | y  ≥ 0}.

x y

0 0

1  0.25

4 0.5

9 0.75

Factor each polynomial. If the polynomial cannot be factored, write prime .

68. x2 − 81

SOLUTION:  

69. a2 − 121

SOLUTION:  

70. n2 + 100

SOLUTION:  This is the sum of two squares, not the difference. Therefore it cannot be factored and is a prime polynomial.

71. −25 + 4y2

SOLUTION:  

72. p4 − 16

SOLUTION:  

73. 4t4 − 4

SOLUTION:  

74. PARKS  A youth group traveling in two vans visited Mammoth Cave in Kentucky. The number of people in each van and the total cost of the cave are shown. Find the adult price and the student price of the tour.

SOLUTION:  Let x = the price of the adult ticket and y = the price of the student ticket. In Van A, there were 2 adults and 5 students, and the total cost was $77.  In Van B, there were 2 adults and 7 students, and the total cost was $95.   2x + 5y = 77 2x + 7y = 95   Because 2x and 2x have the same coefficient, elimination using subtraction is the best method.

  Now, substitute 9 for y in either equation to find x.

  So, the price of the adult ticket was $16 and the price of the student ticket was $9.

Solve each equation.75. 6x = 24

SOLUTION:  

76. 5y − 1 = 19

SOLUTION:  

77. 2t + 7 = 21

SOLUTION:  

78. 

SOLUTION:  

79. 

SOLUTION:  

80. 

SOLUTION:  

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11-7 Mixed Expressions and Complex Fractions