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y
x
–6
–14
–2 1 4
4(4, 2)
(2, –2)
(0, –6)
(–2, –10)
–4, –14)
(3, 0)
2x – y = 6
Answers to Odd-Numbered Problems
x
y
–2
–6
–6 2
6
10
14
6
(4, 12)
(2, 8)
(0, 4)(–2, 0)
(–4, –4)
y = 2x + 4
(–2, 3)
4
(2, 1)
321–1
x
43
1
–1–2
y
–2
19. m � � A slope of � means thatfor every 2 unit change in x, ywill change (�1) unit.
12
12
21. m � 0 A slope of 0 means that regardless how x changes, yremains constant.
(2, –1)(–3, –1)
31–1–2
x
321
–2–3
y
(–1, 2)
(–1, –2)
3 41 2–2–3
x
3
4
21
–2–3
y23. The slope is not defined.
7.x 0 3 2 �2 4 �4
y �6 0 �2 �10 2 �14
CHAPTER 1 Linear Equations
Exercise 1.1 (p. 15)
1. A � (4, 2); B � (6, 2); C � (5, 3); D � (�2, 1); E � (�2, �3);F � (3, �2); G � (6, �2); H � (5, 0)
3. The set of points of the form (2, y), where y is a real number, isa vertical line passing through (2, 0) on the x-axis.
5.x 0 �2 2 �2 4 �4
y 4 0 8 0 12 �4
4
(2, 4)
(2, –1)
(2, –3)
(2, 1)(2, 0)
31–1–2–3
x
4321
–1–2–3
y
9. (a) Vertical line: x � 2(b) Horizontal line: y � �3
11. (a) Vertical line: x � �4(b) Horizontal line: y � 1
13. m � A slope of means that for every 2 unit change in x,y changes 1 unit.
15. m � �1 A slope of �1 means that for every 1 unit changein x, y changes by (�1) units.
17. m � 3 A slope of 3 means that for every 1 unit change in x, y will change 3 units.
12
12
54
(1, 0)
(2, 3)
32–1
x
y
1
321
–1–2–3
AN-2 Answers to Odd-Numbered Problems
25. 27. 59. slope: m � ; y-intercept: (0, �2)23
(1, 2)
(2, 4)
3 41 2–1–2
x
4
21
–2
y
rise
run
x
y(–2, 7)
(2, 4)
–3 –1–1
1
3
5
7
1 3
rise
run
29. 31.
(–1, 3)
31 2–1–2–3
x
4
21
–2–1
y
(0, 3)
3 41 2–1–2–3
x
4
21
–2–3
–1
y
3
33. x � 2y � 0 35. x � y � 2
37. 2x � y � �9 39. 2x � 3y � �1
41. x � 2y � �5 43. 2x � y � 3
45. 3x � y � �12 47. 4x � 5y � 0
49. x � 2y � 2 51. x � 1
53. y � 4
55. slope: m � 2; y-intercept: (0, 3)
3 41 2–1–2–3
x
4
1
–2–3
–1
y
3
y = 2x + 3
(0, 3)
y
x
y = 2x – 2
–3 –1–1
1
3
–5
–7
1 3
(0, –2)
57. slope: m � 2; y-intercept:(0, �2)
3 41–1–2–3
x12
–1–2
–3
y
34
y = x – 223
(0, –2)
32 41–1–2
x
2
–1–2
y
3
y = –x + 1
(0, 1)
1–1–2–3–5
x1
–1–2–3–4–5
y
x = –4
(–4, 0)
31 2–1–2–3
x
4
6
23
1
y
y = 5
(0, 5)
61. slope: m � �1; y-intercept: (0, 1)
63. Slope is not defined; there is no y-intercept.
65. slope: m � 0; y-intercept: (0, 5)
67. slope: m � 1; y-intercept: (0, 0)
31 2–1–2–3
x
23
1
–2–3
–1
y y = x
(0, 0)
69. slope: m � ; y-intercept: (0, 0)32
31 2–1–2–3
x
23
1
–2–3
y y = x32
(0, 0)
71. y � �3 73. C � 0.122x
Exercise 1.2 AN-3
75. (a) C � 0.08275x � 7.58, 0 � x � 400(b)
(c) The monthly charge for using 100 KWH is $15.86.(d) The monthly charge for using 300 KWH is $32.41.(e) The slope indicates that for every extra KWH used (up
to 400 KWH), the electric bill increases by 8.275 cents.
77. w � 4h � 129 79. C � 0.53x � 1,070,000
81. (a) C � (F � 32) (b) C � 20°
83. (a) y �� t � 53.007 (b) y � 52.74 billion gallons(c) The slope tells us that the reservoir loses 1 billion gallons
of water every 75 days.(d) y � 52.594 billion gallons(e) In 10.89 years the reservoir will be empty.
85. Window: X min � �10; X max � 10Y min � �10; Y max � 10
175
59
x
y
00 200 400
20
40
(100, $15.86)
(300, $32.41)
–10
–10
10
10
–10
–10
10
10
x-intercept: (1.67, 0); y-intercept: (0, 2.50)
87. Window: X min � �10; X max � 10Y min � �10; Y max � 10
x-intercept: (2.52, 0); y-intercept: (0, �3.53)
89. Window: X min � �10; X max � 10Y min � �10; Y max � 10
–10
–10
10
10
–10
–10
10
10
91. Window: X min � �10; X max � 10;Y min � �10; Y max � 10
x-intercept: (0.78, 0); y-intercept: (0, �1.41)
93. (b)
95. (d)
97. y � x � 2 or x � y � �2
99. y � � x � 1 or x � 3y � 3
101. (b), (c), (e), (g)
103. y � 0
105. Answers vary.
107. No; no.
109. The lines are identical.
111. Two lines can have the same y-intercept and the same x-intercept but different slopes only if their y-intercept isthe point (0, 0).
Exercise 1.2 (p. 25)
1. parallel 3. intersecting 5. coincident
7. parallel 9. intersecting 11. intersecting
13
13. (3, 2) 15. (3, 1)
y
x(3, 2)
–3 –1
3
7
–5
–9
1 5
L M
(3, 1)
x
y
L
M
–5 –2
–3
1
5
1 4
x-intercept: (2.83, 0); y-intercept: (0, 2.56)
AN-4 Answers to Odd-Numbered Problems
17. (1, 0) 19. (2, 1)
21. (�1, 1) 23. (4, �2)
43
(1, 0)
2–1
x
4
21
–1–2
yL M
43
(2, 1)
21–1–2
x
3
1
–2–3
y LM
3
(–1, 1)
21–1–3
x
3
1
–2–3
y LM
3 5
(4, –2)
21–1–2
x
3
12
–1
–3
y L
M
25. m1m2 � � (�3) � �1 27. m1m2 � � � (2) � �1
29. m1m2 � � (4) � �1 31. y � 2x � 3 or 2x � y � 3
33. y � � x � or x � 2y � 9
35. y � 4x � 6 or 4x � y � �6
37. y � 2x or 2x � y � 0 39. x � 4
41. y � � x � or x � 2y � �5
43. y � � x � or 15x � 30y � 19
45. t � 4 47. y � x � 49. (c)
Exercise 1.3 (p. 33)
1. (a) S � $80,000(b) S � $95,000(c) S � $105,000(d) S � $120,000
3. (a) y � 650x � 1,287,500(b) The average cost of a compact car is predicted to be
$15,750.(c) The slope can be interpreted as the average yearly
increase in price of a compact car.
5. (a) S � t �
(b) The predicted average SAT score will be 492.
7. (a) P � 0.53t � 1034.4(b) 27.7%(c) The slope is the annual percentage increase of the popu-
lation over 25 who hold bachelor’s degrees or higher.
16,5947
107
8519
519
1930
12
52
12
92
12
14
12
13
6050403020
(30, 900)
R
C
100
10001200
800600400200
0
y
xLoss
Profit
x
y
20000
50
100
150
200
400 600 800
RC
(500, 150)
Profit
Loss
9. The break even point is x � 30.
13. The break even point occurs when x � 1200 items are pro-duced and sold.
2000
1500
1000
500
00 1000 2000
x
y
(1200, 1200)
Loss
Profit
R
C
15. (a) The revenue from delivering x newspapers is given by R � $1.79x
(b) The cost of delivering x newspapers is given by C � $0.53x � $1,070,000
(c) The profit from delivering x newspapers is given byP � 1.26x � 1,070,000
(d) (849207, 1520080) The company breaks even when849,207 newspapers are delivered.
(e)
(f)
yx
1,000,000
300,000
0–200,000
–700,000
–1,200,000
P(849206, 0)
y
x
R
C2,000,000
1,500,000
1,000,000
500,000
00 1,000,000
(849207, 1520080)
11. The break even point is x � 500.
Exercise 1.4 AN-5
17. To break even put 20 caramels and 30 creams into each box;increase the number of caramels to obtain a profit.
19. Mr. Nicholson should invest $50,000 in AA Bonds and$100,000 in Savings and Loan Certificates.
21. Mix 25 pounds of Kona coffee with 75 pounds of Colombiancoffee to obtain a blend worth $10.80 per pound.
23. Mix 30 cubic centimeters of the 15% solution with 70 cubiccentimeters of the 5% solution to obtain a solution that is8% acid.
25. The market price is $1.00.
27. The market price is $10.00.
29. (a) Market price: $1.00(b) Supply demanded at market price: 1.1 units(c)
31. D � �4p � 23
Exercise 1.4 (p. 40)
1. A relation exists, and it appears to be linear.
3. A relation exists, and it appears to be linear.
5. No relation exists.
7. (a) (b) y � 2x � 2
(c)
x
y
–2
4
8
12
16
20
2 4 6 8 10
p
y
(1, 1.1)
S
D
3
2
1
00 1 2 3
(d) Window: X min � �2; X max � 10Y min � �3; Y max � 20
x
y
–2
4
8
12
16
20
2 4 6 8 10
–2
–3
20
10
(e) Using the LinReg program, the line of best fit is:y � 2.0357x � 2.3571.
(f)
–2
–3
20
10
9. (a)
(b) y � x �
(c)
(d) Window: X min � �6; X max � 6Y min � �6; Y max � 7
x
y
–6
–6
2
6
–2 2 6
12
94
x
y
–6
–6
2
6
–2 2 6
–6
–6
7
6
(e) Using the LinReg program, the line of best fit is:y � 2.2x � 1.2.
AN-6 Answers to Odd-Numbered Problems
(f)
11. (a) (b) y � � x � 115
(c)
(d) Window: X min � 0; X max � 100Y min � 1; Y max � 120
y
x0
0 20 40 60 80 100
20
40
60
80
100
34y
x0
0 20 40 60 80 100
20
40
60
80
100
–6
–6
7
6
(b) y � 4x � 180(c)
(d) Window: X min � �30; X max � 10Y min � 0; Y max � 160
x
y
0
150
100
50
10–10–30 30
01
120
100
(e) Using the LinReg function the line of best fit is:y � �0.72x � 116.6.
(f)
13. (a)
x
y
0
150
100
50
10–10–30 30
01
120
100
–300
160
10
(e) Using the LinReg function, the line of best fit is:y � 3.86131x � 180.29197.
(f)
15. (a)
(b) C � I �
(c) The slope of this line indicates that a family will spend$23 of every extra $30 of disposable income.
(d) A family with a disposable income of $42,000 is predictedto consume $32,867 worth of goods.
(e) Using the LinReg function on the graphing utility, theline of best fit is: y � 0.75489x � 0.62663
17. (a) Window: X min � 0; X max � 75.5 (thousand)Y min � 0; Y max � 236.5 (thousand)
23
2330
00 20,000 40,000 60,000
20,000
40,000
60,000C
l
–300
160
10
00
236.5
75.5
Chapter 1 Review Exercises AN-7
(b) Using the LinReg function, the line of best fit is:y � 2.98140x � 0.07611.
(c)
(d) The slope indicates that a person can borrow an addi-tional $2.98 for each additional dollar of income.
(e) $125,143
19. (a) Window: X min � �10; X max � 110Y min � 50; Y max � 70
00
236.5
75.5
(b) Using the LinReg function, the line of best fit is:y � 0.07818x � 59.0909.
(c)
(d) The slope indicates the apparent change in temperaturein a 65°F room for every percent increase in relativehumidity.
(e) The apparent temperature of a room with an actual tem-perature of 65°F remains at 658. when the relative humi-tity is 75%.
–1050
70
110
–1050
70
110
CHAPTER 1 Review
True–False Items (p. 43)
1. F 2. T 3. T 4. F
5. F 6. T 7. F 8. T
9. F 10. F
Fill in the Blanks (p. 43)
1. abscissa; ordinate, or x-coordinate; y-coordinate
2. Undefined; zero 3. negative
4. parallel 5. coincident
6. perpendicular 7. intersecting
Review Exercises (p. 44)
1.
x
y
–4 –2
–2
2
–4
42
(0, 3)
(2, –1)
y = –2x + 3
3.
5. (a) m � � ; A slope � � means that for every 2 units x moves to the right, y moves down 1 unit.
(b) y � � x � or x � 2y � 5
(c)
7. (a) m � 2; A slope � 2 means that for every 1 unit changein x, y changes 2 units.
(b) y � 2x � 7 or 2x � y � �7(c) y
x
P
Q
–2–2 2 4 6
2
4
72x – y = –7
y
xP
Q
–3–2
2
4
5
x + 2y = 5
52
12
12
12
2 31–1
2y = 3x + 6
–3
x
21
y
3(0, 3)
(–2, 0)
AN-8 Answers to Odd-Numbered Problems
9. y � �3x � 5 or 3x � y � 5
11. y � 4
13. x � 8
15. y � � x � 5 or 5x � 2y � 10
17. y � � x � 4 or 4x � 3y � �12
19. y � � or 2x � 3y � �1
y
x
(–5, 3)
(–2, 1)run
rise
–5 –2 3
3
–3
2x + 3y = –1
23 x �1
3
x
y
–3
–2
2
–4
3
(–3, 0)
(0, –4)
4x + 3y = –12
43
x
y
–4 –2–2
2
4
–4
4
(0, 5)
(2, 0)
(4, –5)
y = x + 552
52
–4
–4
4
8
4
y
x
(8, 5)
x = 8
x
y
–2
–4 –2
2
2 4
(–3, 4)
y = 4
y
x
rise
run
(1, 2)
(2, –1)
(3, –4)
3x + y = 5
–4
–4 –2–2
2
4
21. y � x � or 3x � 2y � �21
23. m � � , y-intercept (0, 9)
25. m � �2, y-intercept: (0, )
27. parallel 29. intersecting 31. coincident
33. (5, 1)
35. (1, 3) y
x(1, 3)
–4 4
–4
8M L
y
x(5, 1)
L
M–4
–4
–8
8
4 8
321–1–2–3
x
6
4
2
–2
y
4x + 2y = 9
92(0, )
94( , 0)
92
5439x + 2y = 18
1
x
810
642
y
2
(0, 9)
(2, 0)
92
3x – 2y = –21
y
x(–5, 3)
–4–4
4
12
–8
4–12 8
212(0, )
212
32
Chapter 1 Review Exercises AN-9
37. (�2, 1)
39. Invest $78,571.43 in B-rated bonds and $11,428.57 in thewell-known bank.
41. (a) 120 people need to attend for the group to break even.(b) 300 people need to attend to achieve the $900 profit.(c) If tickets are sold for $12.00 each 86 people must attend
to break even, and 215 people must attend to achieve aprofit of $900.
43. Relation does not appear to be linear.(a)
45. (a)
(b) m � �0.2733
8
6
4
2
1987 1989 1991 1993
Car
bon
mon
oxid
e
Year
90
45
1 3 5 7
y
x
(–2, 1)
–1–2–3–4
x
L
M
34
1
–1–2
y
2
(c) The slope indicates the average annual decrease in con-centration of carbon monoxide between 1987 and 1990.
(d) m � �0.33(e) The slope indicates the average annual decrease in con-
centration of carbon monoxide between 1990 and 1993.(f) m � �0.308(g) The slope indicates the average annual decrease in the
concentration of carbon monoxide.(h) The trend indicates that the average level of carbon
monoxide is decreasing.
47. (a)
(b) The relation appears to be linear.(c) m � 22.05(d) The slope represents the average annual increase in
value of a share of the Vanguard 500 Index Fund from1996 to 1999.
(e) y � 22.236x � 46.54 (f) $179.96
Mathematical Questions from Professional Exams
1. b 2. d 3. d 4. d
5. c 6. c 7. b 8. b
150
100
50
1996 1997 1998 1999Year
Val
ue
Exercise 2.1 AN-9
37. (�2, 1)
39. Invest $78,571.43 in B-rated bonds and $11,428.57 in thewell-known bank.
41. (a) 120 people need to attend for the group to break even.(b) 300 people need to attend to achieve the $900 profit.(c) If tickets are sold for $12.00 each 86 people must attend
to break even, and 215 people must attend to achieve aprofit of $900.
43. Relation does not appear to be linear.(a)
45. (a)
(b) m � �0.2733
8
6
4
2
1987 1989 1991 1993
Car
bon
mon
oxid
e
Year
90
45
1 3 5 7
y
x
(–2, 1)
–1–2–3–4
x
L
M
34
1
–1–2
y
2
(c) The slope indicates the average annual decrease in con-centration of carbon monoxide between 1987 and 1990.
(d) m � �0.33(e) The slope indicates the average annual decrease in con-
centration of carbon monoxide between 1990 and 1993.(f) m � �0.308(g) The slope indicates the average annual decrease in the
concentration of carbon monoxide.(h) The trend indicates that the average level of carbon
monoxide is decreasing.
47. (a)
(b) The relation appears to be linear.(c) m � 22.05(d) The slope represents the average annual increase in
value of a share of the Vanguard 500 Index Fund from1996 to 1999.
(e) y � 22.236x � 46.54 (f) $179.96
Mathematical Questions from Professional Exams
1. b 2. d 3. d 4. d
5. c 6. c 7. b 8. b
150
100
50
1996 1997 1998 1999Year
Val
ue
Exercise 2.1 (p. 62)
1. Yes 3. No 5. Yes 7. Yes 9. Yes
11. The solution of the system is x � 6 and y � 2.
13. The solution of the system is x � 3 and y � 2.
15. The solution of the system is x � 8 and y � �4.
17. The solution of the system is x � and y � � .
19. The system is inconsistent.
21. The solution of the system is x � 1 and y � 2.
16
13
CHAPTER 2 Systems of Linear Equations; Matrices.
23. The solutions of the system are y � � x � 2 and x where xis any real number, or as x � �2y � 4 and y, where y is anyreal number.
25. The solution of the system is x � 1 and y � 1.
27. The solution of the system is x � and y � 1.
29. The solution of the system is x � 4 and y � 3.
31. The solution of the system is x � and y � .
33. The solution of the system is x � 8, y � 2, and z � 0.
35. The solution of the system is x � 2, y � �1, and z � 1.
15
43
32
12
AN-10 Answers to Odd-Numbered Problems
37. The system is inconsistent.
39. The solutions of the system are x � 5z � 2, y � 4z � 3, andz, where z is any real number.
41. The system is inconsistent.
43. The solution of the system is x � 1, y � 3, and z � �2.
45. The solution of the system is x � �3, y � , and z � 1.
47. The dimensions of the floor should be 30 ft � 15 ft.
49. They should plant 219.8 acres of corn and 225.2 acres ofsoybeans.
51. 22.5 pounds of cashews should be mixed with the peanuts.
53. A bowl of noodles costs 571 yen and a carton of milk costs220 yen.
55. The amount of the refund should be $5.56.
57. 50 mg of the first liquid (20% vitamin C and 30% vitaminD) should be mixed with 75 mg of the second liquid.
59. Use 9.16 pounds of rolled oats and 8.73 pounds of molasses.
61. The theater has 100 orchestra seats, 210 main seats, and 190balcony seats.
63. Kelly should invest $8000 in treasury bills, $7000 in treasurybonds, and $5000 in corporate bonds.
Exercise 2.2 (p. 78)
1. 3.
5. 7.
9.
11.
13.
15. (a) (b)
17. (a) (b)
19. (a) (b) �120
�3�5�8
167
� �2�2
0�� 10
�3
�311
144
� �226�
�120
�3�5
�15
238
� �6�4
�12�� 10
�3
�31
�6
2�1
2 � �6
86�
�120
�35
�6
46
16 � 3
615�� 1
0�3
�313
4�2
4 � 30
6��1
0�3
1 � �2
9��1
2�1
31
�1�1
4 � 05�
�410
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21.
The system is consistent and the solution is x � 7 and y � �1.
23.
The system is inconsistent.
25.
The system is consistent and has an infinite number of solu-tions. The solutions are x � �2z � �1, y � 4z � 2, and z,where z is any real number.
27.
The system is consistent. The solutions are x1 � �17x4 � 24,x2 � 7x4 � 10, x3 � �2x4 � 3, and x4, where x4 is any realnumber.
29.
The system is consistent. The solutions are x1 � 2x3 � 2x4 �4, x2 � �x3 � 3x4 � 3, x3 and x4, where x3 and x4 are anyreal numbers.
31.
The system is consistent. The solutions are x1 � x4 � 2,x2 � x4 � 2, x3 � x4, and x4, where x4 is any real number.
33. The solution of the system is x � 2 and y � 4.
35. The solution of the system is x � 2 and y � 1.
37. The solution of the system is x � 2 and y � 1.
39. The system is inconsistent.
41. The solution of the system is x � and y � .
43. The solutions of the system are y � � x � and x, where x is any real number, or x � �3y � 2 and y where y is anyreal number.
45. The solution of the system is x � 2 and y � 3.
47. The solution of the system is x � and y � .
49. The solution of the system is x � 1, y � 4, and z � 0.
51. The solution of the system is x � , y � � , and z � 6.
53. The solution of the system is x � 2, y � �1, and z � 1.
55. The system is inconsistent.
125
85
13
23
23
13
13
12
�x 1 � 2x 2 � x 4 � �2x 2 � 3x 3 � 2x 4 � 2
x 3 � x 4 � 00 � 0
�x 1 � 2x 2 � 4x 4 � 2x 2 � x 3 � 3x 4 � 3
0 � 0
�x 1 � 2x 2 � x 3 � x 4 � 1x 2 � 4x 3 � x 4 � 2
x 3 � 2x 4 � 3
�x � 2z � �1y � 4z � �2
0 � 0
�x � 2y � 3z � 1y � 4z � 2
0 � 3
�x � 2y � 5y � �1
Exercise 2.3 AN-11
57. The solution of the system is x � , y � , and z � 1.
59. The solution of the system is x � , y � � , and z � .
61. The solution of the system is x � 2, y � �1, and z � 3.
63. The solution of the system is x1 � 20, x2 � �13, x3 � , andx4 � .
65. A mezzanine ticket costs $54, a lower balcony ticket costs$38, and a middle balcony ticket costs $30.
67. There are 10 work stations set up for 2 students and 6 workstations set up for 3 students.
69. Carletta should invest $4000 in treasury bills, $4000 in trea-sury bonds, and $2000 in corporate bonds.
71. The meal should consist of 1 serving of chicken, 1 serving ofpotatoes, and 2.5 servings of spinach.
73. 20 cases of orange juice, 12 cases of tomato juice, and 6 casesof pineapple juice are prepared.
75. The teacher should order 2 of the first package (20 white, 15blue, 1 red), 10 of the second package (3 blue, 1 red), and 4of the third package.
77. The recreation center should purchase 4 assorted cartons, 8mixed cartons, and 5 single cartons.
79. To fill the order use 2 large cans, 1 mammoth can, and 4giant cans.
83. Answers will vary.
Exercise 2.3 (p. 90)
1. No, the second row contains all zeros; it should be at thebottom.
3. No, there is a 1 above the leftmost 1 in the 2nd row. It shouldbe a 0.
5. No, the leftmost 1 in the 2nd row is not to the right of theleftmost 1 in the 1st row.
7. Yes 9. Yes 11. Yes
13. Infinitely many solutions, x � �y � 1 and y, where y is anyreal number.
15. One solution, x � 4 and y � 5.
17. Infinitely many solutions, x � 2z � 6, and y � �3z � 1,and z, where z is any real number.
19. Infinitely many solutions, x � �2y � 1, y, and z � 2, wherey is any real number.
21. Infinitely many solutions, x � 1, y � 2, and z, where z, is anyreal number.
23. One solution, x � �1, y � 3, and z � 4.
25. Infinitely many solutions, x � z � 1, y � �2z � 1, and z,where z is any real number.
252
12
29
23
29
23
13 27. Infinitely many solutions, x1 � x4 � 4, and x2 � �2x3 �
3x4, x3, and x4, where x3 and x4 are any real numbers.
29. The solution of the system is x � 2 and y � 1.
31. The system is inconsistent.
33. The solutions of the system are x � 2y � 4,
where y is any real number.
35. The solutions of the system are x � �3
y � �3z � 5, and z, where z is any real number.
37. The solution of the system is x � 3, y � 2,
and z � �4.
39. The solution of the system is
x1 � �17, x2 � 24, x3 � 33, and x4 � 14.
41. The solution of the system is
x1 � x4 � , x2 � x4 � , x3 � � x4 � , and x4, where x4 is any real number.
43. The system is inconsistent.
45. The system is inconsistent.
47. The solution of the system is x1 � 1,
x2 � 2, x3 � 0, and x4 � 1.
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AN-12 Answers to Odd-Numbered Problems
49. The system is inconsistent.
51. The solutions of the system are x � 0,
y � z � 6, and z, where z is any real number.
53.
Amount in EE/E Amount in I Amount in HH/H
$ 0 $17,000 $8,000
$ 3,125 $14,875 $7,000
$ 6,250 $12,750 $6,000
$ 9,375 $10,625 $5,000
$12,500 $ 8,500 $4,000
$15,625 $ 6,375 $3,000
$18,750 $ 4,250 $2,000
$21,875 $ 2,125 $1,000
$25,000 $ 0 $ 0
55. Yes, the couple can still maintain their goals.
Amount in EE/E Amount in I Amount in HH/H
$ 0 $6,250 $18,750
$2,000 $4,550 $18,450
$4,000 $2,850 $18,150
$6,000 $1,150 $17,850
$7,353 $ 0 $17,647
57. There is insufficient information to determine the price ofeach food item.
Hamburger Large Fries Large Cola
$2.15 $0.88 $0.60
$2.10 $0.90 $0.65
$2.05 $0.92 $0.70
$2.00 $0.93 $0.75
$1.95 $0.95 $0.80
$1.90 $0.97 $0.85
$1.85 $0.98 $0.90
�100
010
0�1
0 � 0
�60�
�100
010
010
� 001�
59. (a) The couple invests $20,000.
Treasury Bills Corporate Bonds Junk Bonds
$ 0 $10,000 $10,000
$1,000 $ 8,000 $11,000
$2,000 $ 6,000 $12,000
$3,000 $ 4,000 $13,000
$4,000 $ 2,000 $14,000
$5,000 $ 0 $15,000
(b) The couple invests $25,000.
Treasury Bills Corporate Bonds Junk Bonds
$12,500 $12,500 $ 0
$13,500 $10,500 $1,000
$14,500 $ 8,500 $2,000
$15,500 $ 6,500 $3,000
$16,500 $ 4,500 $4,000
$17,500 $ 2,500 $5,000
$18,500 $ 500 $6,000
$18,750 $ 0 $6,250
(c) Even if all $30,000 are invested in treasury bills (the invest-ment with the lowest return), the interest income is $2100.
61.
Number of Number of Number of mg of 20% C, mg of 40% C, mg of 30% C, 30% D liquid 20% D liquid 50% D liquid
50 75 0
41.25 75.625 5
32.5 76.25 10
23.75 76.875 15
15 77.5 20
6.25 78.125 25
0 78.571 28.571
63. Answers will vary.
Exercise 2.4 (p. 103)
1. 2 � 2, a square matrix
3. 2 � 3 5. 3 � 2 7. 3 � 2
9. 2 � 1, a column matrix
Exercise 2.5 AN-13
11. 1 � 1, a column matrix, a row matrix, and a square matrix
13. False; the dimensions must be the same for two matrices tobe equal.
15. True 17. True 19. True 21. True
23. False; the dimensions must be the same for two matrices tobe equal.
25. 27.
29. 31.
33. 35.
37. 39.
41. 43.
45.
47.
49.
51. x � �4 and z � 4
53. x � 5 and y � 1
55. x � 4, y � �6, and z � 6
57.
59.
61.
63.
65. ,
Yes, a 4 � 2 matrix could represent the situation.
MaleFemale
�Associates
218,000364,000
Bachelor ,s573,000714,000
Master , s181,000261,000
Doctoral26,70020,400�
�Local
542,97870,556
State1,154,869
81,607
Fed135,237
10,179�MaleFemale
�37
420.529
�179
1618
3013
�322
151
3143�
�19
�1215.5
�29
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10
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19�14
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��
�24
�3.512
168
�1
77
�47
55
136�
2B � 3B � � 525
�105
010� � 5B
A � (�A) � �00
00
00� � 0
A � B � �35
�53
43� � B � A
� 23�17
�7�1
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13
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28�17
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67.
69.
Exercise 2.5 (p. 114)
1. [14] 3. [4] 5. [18 �8]
7. 9. [4 6] 11.
13. 15.
17. BA is defined and is a 3 � 4 matrix.
19. AB is not defined.
21. (BA)C is not defined.
23. BA � A is defined and is a 3 � 4 matrix.
25. DC � B is defined and is a 3 � 3 matrix.
27. 29.
31.
33. 35.
37. 39.
41.
43.
45.
47. �6671
165158
7413
124.5�3
94106
79152
38285246�
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861369.5412.5
251350115882
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143420215491
��
0.52119.5
�9.5
1614
845
�3028
�23�9
25643383�
D(CB) � ��61
�7
4220
4
�96
�18� � (DC)B
� 1015
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301620
3750
�8���14�20
7�6�
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ENG225
75
EDUC80
120 �MaleFemale
�Democrats
351203
Republicans271215
Independents7355 �Under $25,000
Over $25,000
AN-14 Answers to Odd-Numbered Problems
49.
51.
53. x � 1 or x � 55. a � d and b � �c
57.
59. Lee spent $372 while Chan spent $257.
61.
63.
67.
A10 �
433.097 �1583.562 �369.817 �216.548 �141.638
1207.695 5998.438 2563.227 �603.847 1045.705
�1423.023 8065.070 4271.798 711.511 2023.364
479.476 �246.538 �231.543 �239.737 �140.557
�899.341 �3064.313 �1627.502 449.670 �698.609
A15 �
�2247.845 �118449.318 �69122.364 1123.922 �32134.304
�11094.809 542433.513 249928.402 5547.405 110820.210
100366.783 831934.563 386083.791 �50183.392 165597.136
�18782.297 �38432.094 �18654.086 9391.148 �7395.960
�1633.665 �306291.022 �130154.569 816.833 �56015.454
69. ,
71. Answers will vary.
Exercise 2.6 (p. 126)
1.
3.
5. �121
232
341��
�52
112
2
�1
0
�12
1
�12
� � �100
010
001�
��13
�24�� 2
�32
1�1
2� � �1
001�
�12
23���3
22
�1� � �10
01�
A15 � � 54611092316384
54621092216384
54611092316384�
A10 � �171341512
170342512
171341512�,A2 � �1
12
022
112�
����
A2 � ��2.95�2.8
5.2�1.5
3.6
�0.52.568.6
�1�1.8
�1.212.541.110.3
�0.63
1.61.4
�2.61
�1.8
�0.491.44
�0.260.3
�0.18�
A2 � �10
01�, A3 � �1
001�, and A4 � �1
001�
A2 � �19
04�, A3 � � 1
2108�, and A4 � � 1
450
16�
A2 � � a1 � a
1 � a�a � � � a
1 � a1 � a
�a � � �10
01�
12
AB � �56
�24� � �7
6�3
2� � BA
��5
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23�56
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�249
44122
36187
� 7. 9.
11. 13.
15. 17.
19.
21. ⇒
23. ⇒
25.
27. 29.
31. Inverse does not exist.
33.
35.
37.
39. x � 36, y � �14 41. x � 2, y � 1
43. x � 88, y � �36 45. x � , y � , z �
47. 49. x � � , y � , z �
51. � 0.00540.0104
�0.0193
0.0509�0.0186
0.0116
�0.00660.00950.0344�
169
103
149x � 20
3 , y � 24, z � 563
659
263
149
� 42�9�7
�1843
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213� � � 5
�1
11
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0
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0��1525
25
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1525
35
�15� �
�72
112
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1
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0
16
14�� 2
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120
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18
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32
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14
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63
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19
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Chapter 2 Review Exercises AN-15
53.
55.
57. x � 4.5666, y � �6.4436, z � �24.0747
59. x � �1.1874, y � 2.4568, z � 8.2560
61.
63.
65.
Exercise 2.7: Application 1 (p. 136)
1. A’s wages � C’s wages � $30,000; B’s wages � $22,500
3. A’s wages � $12,000; B’s wages � $22,000; C’s wages �$30,000
5.
7. Farmer’s wages � $20,000;
Builder’s wages � $18,000;
Tailor’s wages � $12,000;
Rancher’s wages � $25,000
9.
Exercise 2.7: Application 2
1. a. THIS IS KILLING MY GPAb. EVERYONE LOVES MICKEY
3. WHATS YOUR EMAIL ADDRESS
5. a. 21 11 47 27 57 33 49 28 85 50 35 22 80 47 85 55b. 61 33 101 61 84 50 64 36 49 31 70 45c. 39 22 97 58 59 37 42 27 48 25 31 20 49 28
X � � 16075.384�
X � �203.282166.977137.847�
��158
2�1�
�015
12
� 110�
AA�1 � �ac
bd�� d
�c
�ba� � �1
001�
�54
516
7732 �41
161732
�12
38
1116 �7
87
16
74 � 3
16 �9132
4716 �23
32
�32
18
4916 �21
85
16
14 � 1
16 � 932
516
332
�0.0249
�0.01710.0206
�0.0175
�0.03600.05210.00820.0570
�0.00570.0292
�0.04210.0657
0.0059�0.0305
0.00050.0619
�Exercise 2.7: Application 3
1.
Indirect Costs forServices from
Total Direct DepartmentsCosts Costs, Dollars
Department Dollars Dollars S1 S2
S1 3109.10 2000 345.46 763.63
S2 2290.90 1000 1036.37 254.54
P1 3354.55 2500 345.46 509.09
P2 2790.91 1500 1036.37 254.54
P3 3854.55 3000 354.46 509.09
Totals 15,400.01 10,000 3109.12 2290.89
Total of the service charges allocated to P1, P2, and P3:$3000.01
Sum of the direct costs of the service departments, S1, and S2:$3000
Exercise 2.7: Application 4 (p. 149)
1. 3.
5.
7. a. y � �
b. 17,743 units will be supplied.
9. y � 1.4978x � 36.1345
11. a. Not symmetricb. Symmetricc. Not symmetricYes, for two matrices to be equal, they must have the samedimensions.
275
5435 x
[8 6 3]
� 111
012
14��4
12
310�
CHAPTER 2 Review
True–False Items (p. 151)
1. T 2. F 3. F 4. T 5. F 6. F 7. F
Fill in the Blanks (p. 151)
1. 3 � 2 2. one; infinitely many 3. rows; columns
4. inverse 5. 3 � 3 6. 5 � 5
Review Exercises (p .181)
1. x � 2, y � �1
3. x � 2, y � �1
� �
AN-16 Answers to Odd-Numbered Problems
5. No solution, the system is inconsistent.
7. x � �1, y � 2, z � �3
9. x � � , y � � , and z, where z is any real number.
11.
13.
15. x � , y �
17. x � �103, y � 32, z � 9
19. x � 29, y � �10, z � �1
21. No solution, the system is inconsistent.
23. x � 9, y � � , z � �
25. x � 29, y � 8, z � �24
27. x � , y � � , and z, where z is any real number.Answers will vary. Three possible solutions are x � , y �� , when z � 0; x � , y � � , when x � 1; and x � 1, y ��2, when z � �1.
29. x � � � 1, y � � 2, and z, where z is any real number.Answers will vary.
31. No solution, the system is inconsistent.
33. One solution, x � 11, y � �1, and z � �1.
35. Infinitely many solutions, x1 � �2x4 � 1, x2 � �2x4 � 1,x3 � 3, and x4, where x4 is any real number.
37. The dimensions are 3 � 2.
39. The dimensions are 3 � 2.
41. The dimensions are 3 � 3.
43. The dimensions are 3 � 3.
45. The dimensions are 3 � 3.
47. The dimensions are 2 � 3.�10
24
�12�
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8�18
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918
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8� 10
4�� 4
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5
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02412�
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�490�
45 z3
5 z
47
137
97
107
97
57 z3
7 z � 107
373
563
269
149
�x � 4y � 6z � �1
�3x � 2y � 8x � 4y � �1
698
98 z
394
74 z
49. . The dimensions are 3 � 2.
51.
53. Inverse does not exist.
55.
57. AB � BA when x � w and y � �z.
59. Each box should contain 20 caramels and 30 creams. Toobtain a profit, increase the number of caramels in each box,(decreasing the number of creams.)
61.
Small Box Medium Box Large Box
0 66.67 33.33
5 60 35
20 40 40
35 20 45
50 0 50
63. a. To attain $2500 per year in income.
Treasury Bills Corporate Bonds Junk Bonds
$35,000 $5,000 $ 0
$35,500 $4,000 $ 500
$36,000 $3,000 $1,000
$36,500 $2,000 $1,500
$37,000 $1,000 $2,000
$37,500 $ 0 $2,500
b. To attain $3000 per year in income.
Treasury Bills Corporate Bonds Junk Bonds
$10,000 $30,000 $ 0
$13,000 $24,000 $ 3,000
$16,000 $18,000 $ 6,000
$19,000 $12,000 $ 9,000
$22,000 $ 6,000 $12,000
$25,000 $ 0 $15,000
�1
163
16
� 316
1323
321332
14
�1414
�
�1323
0
1��3
15
�45
�2� � C
Exercise 3.1 AN-17
c.
Treasury Bills Corporate Bonds Junk Bonds
$ 0 $25,000 $15,000
$ 2,500 $20,000 $17,500
$ 5,000 $15,000 $20,000
$ 7,500 $10,000 $22,500
$10,000 $ 5,000 $25,000
$12,500 $ 0 $27,500
65. a.
b. y � 4096.7742x � 245,870.9677c. The number of people that emigrate is increasing by 4097
(rounding to the nearest person) people each year.
0
245,000
255,000
265,000
275,000
285,000
295,000
5 10 15
d. An estimated 307,323 people will emigrate in 2005.e. An estimated 266,355 people emigrated in 1995.f. y � 4096.7742x � 245,870.9677
67. 275.564 units of A, 98.86 units of B, and 179.548 units of Cshould be produced.
69.
Total Direct Indirect Costs for Department Costs (in Cost Services
Dollars) In Dollars (in Dollars)
S1 1745.45 800 349.09 596.36
S2 5963.64 4000 174.55 1789.09
P1 2445.45 1500 349.09 596.36
P2 2216.37 500 523.64 1192.73
P3 3338.18 1200 349.09 1789.09
Totals 15,709.09 8000 1745.46 5963.63
Mathematical Questions from Professional Exams
1. b 2. b 3. d 4. c
CHAPTER 3 Linear Programming: Geometric Approach
Exercise 3.1 (p. 168)
1. 3.
5. 7.
9. 11.
x
6
–2
y
6–6
5x + y = 10
10
(0, 0)
–2
x
4
2
–2
y
2
2x + 3y = 6
(0, 0)–1–2–3–4
x
34
2
y
21 3 4
y = 1
(0, 0)
–1–2
x
34
12
–1–2–3–4
y
21 3 5
x = 4
(0, 0)x
y
–4 –2
–2
2
4
–4
42
(1, 1)
x = 0
13. P1 is part of the graph of the system, P2 and P3 are not.
15. P1 and P3 are part of the graph of the system, P2 is not.
17. b 19. c 21. d 23. c
25. Unbounded. Corner points: (2, 0), (0, 2).
27. Bounded. Corner points: (2, 0), (3, 0), (0, 2).
3–2
x
2
–2
y
2x + 3y = 6
x + y = 2
(0, 2)
(3, 0)
(2, 0)
x
y
–4
–2
2
4
–4
42
(0, 2)
(0, 0)
(2, 0)
x + y = 2
y = 0
x = 0
654321–1–2–3
x
32
x + 5y = 5
–1
y
(0, 0)
AN-18 Answers to Odd-Numbered Problems
29. Bounded. Corner points: (2, 0), (5, 0), (2, 6), (0, 8), (0, 2).
31. Bounded. Corner points: (2, 0), (4, 0), ( , ), (0, 4), (0, 2).
33. Unbounded. Corner points: (1, 0), (0, ), (0, 4).
35. Bounded. Corner points: ( , ), (0, 3), (0, 1).
x
y
3x + y = 3
x + 2y = 2
x + y = 4(0, 3)
(0, 1)
35
45( , )
2 4
35
45
y
x
2
3
5
1
–11–1 3 4 5
y = 4
x + 2y = 1
12
x
y
10
8
6
–2–2 10
(0, 4)
(0, 2)
(2, 0) (4, 0)
127
247( , )
3x + y = 12
2x + 3y = 12
x + y = 2
127
247
8642
x
6
10
4
y
(2, 6)
(2, 0)(0, 2)
(0, 8)
(5, 0)
x + y = 2
2x + y = 10
x + y = 8
37.
Corner points: (0, 0), (120, 0), (60, 90), (0, 120).
39. (a)
(b)
Corner points: (0, 0), ( , 0), (0, 40).
41. (a)
(b)
Corner points: (15000, 0), (25000, 0), (15000, 10000).(c) (15000, 0) represents investing $15,000 in treasury bills.
(25000, 0) represents investing $25,000 in treasury bills.(15000, 10000) represents investing $15,000 in treasurybills and $10,000 in corporate bonds.
x
y
(15000, 10000)
(15000, 0) (25000, 0)
x = 15,000
y = 10,000
x + y = 25,000
20,000
5,000
�x � y � 25,000
x 15,000y � 10,000x 0y 0
803
10 20
x
40
30
20
10
y
(0, 0)
(0, 40)
803( , 0)
4x + 3y = 1203x + 2y = 80
�3x � 2y � 804x � 3y � 120
y 0x 0
2201801006020
x
180
60
20
y
(60, 90)(0, 120)
(0, 0)
(120, 0)
3x + 2y = 360
x + 2y = 240
�4x � 8y � 960
12x � 8y � 1440x 0y 0
Exercise 3.3 AN-19
43. (a)
(b)
Corner points: (0, 16), (3, 1), (5, 0).
45. (a)
(b)
Corner points: (0, ), (20, ), (25, 0).
47. Answers will vary.
Exercise 3.2 (p. 178)
1. Maximum of 38 at (7, 8). Minimum of 10 at (2, 2).
3. Maximum of 15 at (7, 8). Minimum of 4 at (2, 2).
5. Maximum of 55 at (7, 8). Minimum of 14 at any point onthe line segment between (2, 2) and (8, 1).
7. Maximum of 53 at (7, 8). Minimum of 14 at (2, 2).
9. Maximum of 81 at (8, 1). Minimum of 22 at (2, 2).
11. Corner points: (0, 4), (3, 0), (13, 0).
13. Corner points: (0, 0), (15, 0), (5, 10), (0, 10).
15. Corner points: (3, 0), (10, 0), (10, 8), (0, 8), (0, 4).
103
703
15105
x
20
10
y3x + 3y = 70
5x + 4y = 85 2x + 3y = 50
(25, 0)
103(20, )
703(0, )
�5x � 4y 853x � 3y 702x � 3y 50
x 0y 0
4 521
x
16
12
8
4
y
(3, 1)
(0, 16)
(5, 0)
x + 2y = 55x + y = 16
�x � 2y 55x � y 16
x 0y 0
17. Maximum of 14 at (0, 2). 19. Maximum of 15 at (3, 0).
21. Maximum of 56 at (0, 8). 23. Maximum of 58 at (6, 4).
25. Minimum of 0 at (0, 0). 27. Minimum of 4 at (2, 0).
29. Minimum of 4 at (2, 0). 31. Minimum of at (0, ).
33. Maximum of 10 at any point on the line x � y � 10 between(0, 10) and (10, 0). Minimum of at ( , ).
35. Maximum of 50 at (10, 0). Minimum of 20 at (0, 10).
37. Maximum of 40 at (0, 10). Minimum of at ( , ).
39. Maximum of 100 at (10, 0). Minimum of 10 at (0, 10).
41. Maximum of 192 at (4, 4). Minimum of 54 at (3, 0).
43. Maximun of 58 at (4, 5). Minimum of 12 at (0, 2).
45. Maximum of 240 at (3, 10).
47. Maximum of 216 at (2, 10).
49. Produce 90 low-grade packages and 105 high-grade packagesfor a maximum profit of $69.
Exercise 3.3 (p. 184)
1. The farmer should plant x acres of soybeans, where 24 �x � 30, and y � 60 � 2x acres of corn for a maximum profitof $9000.
3. She should invest $12,000 in type A bonds and $8000 in typeB bonds for a maximum return of $2400.
5. Manufacture 500,000 of each vitamin for a maximum profitof $75,000.
7. The store should sell 30 microwaves and 20 stoves for a max-imum revenue of $13,000.
9. Purchase 2025 shares of Duke Energy Corp. and 555 sharesof Eastman Kodak for a maximum annual yield of $3267.
11. A child should have 1 of a serving of Gerber Banana PlumGranola and 0.7 of a serving of Gerber Mixed Fruit CarrotJuice for a minimum cost of $1.44.
13. Run the ad for 20 months at the AOL website and 10 monthsat the Yahoo! website to reach a maximum of 2190 millionpeople.
15. Manufacture 25 rolls of low-grade carpet (and no rolls ofhigh-grade carpet) for a maximum income of $2500.
103
103
703
103
103
203
12
32
AN-20 Answers to Odd-Numbered Problems
CHAPTER 3 Review
True–False Items (p. 187)
1. T 2. F 3. T 4. T 5. T 6. F
Fill in the Blanks (p. 187)
1. half plane 2. objective 3. feasible
4. bounded 5. corner point
Review Exercises (p. 187)
1. 3.
5. All 3 points P1, P2, and P3 are part of the graph of the system.
7. a
9. Bounded.
Corner points: (4. 0), (0. 4), (0. 6)
11. Bounded.
Corner points: (0, .2), ( ), (0, .6)85, 65
864
x
8
6
4
y
3x + y = 6
x + 2y = 4
(0, 6)
(0, 2)65
85( , )
642
x
6
2
y
3x + 2y = 12
x + y = 4
(0, 6)
(4, 0)
(0, 4)
y
x2
–2–2 4 6
4
6
8
10 5x + y = 10
–2–4
x
4
2
–2
–4
y
4
x + 3y = 0
13. Bounded.
Corner points: (2, .0), (4, .0), (2, .3), (0, .3), (0, .4)
15. Maximum of at .
17. Minimum of 20 at (0, 10).
19. Maximum of 40 at (20, .0), ( , ), and at any point on theline. 2x � y � 40 connecting them.
21. Minimum of 20 at (10, 0).
23. Maximum of 235 at (5, 8). Minimum of 60 at (4, .0), (0, .3)and at all points on the line 3x � 4y � 12, connecting them.
25. Maximum of 155 at (5, .4). Minimum of 0 at (0, 0).
27. Maximum of 42 at (9, 8).
29. Maximum of 24 at (8, 8).
31. Minimum of at .
33. Produce 8 pairs of downhill skis and 24 pairs of cross-country skis for a maximum profit of $1760.
35. Katy should buy 7.5 lb of food A and 11.25 lb of food B for aminimum cost of $18.75.
37. Give the child 1.58 servings of Gerber Banana Oatmeal andPeach and no Gerber Mixed Fruit Juice for a minimum costof $1.25.
39. Manufacture 550,000 high-potency vitamins and 250,000thousand calcium-enriched vitamins for a maximum profitof $67,500.
Mathematical Questions from ProfessionalExams
1. b 2. a 3. c 4. c 5. d 6. c 7. c
8. b 9. b 10. a 11. b 12. e 13. c 14. b
�45, 18
5 �485
403
403
�403 , 40
3 �803
864
x
6
2
y
(2, 3)
(2, 0)
(4, 0)
(0, 4)
(0, 3)
3x + 2y = 12
3x + 2y = 6x + 2y = 8
Exercise 4.1 AN-21
Section 4.1 (p. 205)
1. Standard 3. Nonstandard
5. Nonstandard 7. Nonstandard
9. Standard 11. Cannot be modified
13. Cannot be modified
15. Constraints
17. 5x1 � 2x2 � x3 � s1 � 20Slack variables 6x1 � x2 � 4x3 � s2 � 24
x1 � x2 � 4x3 � s3 � 16
and initial simplex tableau
19.
The initial simplex tableau is
21.
The initial simplex tableau is:
23. P � 3x1 � 4x2 � 2x3 � 03x1 � x2 � 4x3 � s1 � 5
x1 � x2 � s2 � 5x1 � x2 � x3 � s3 � 6
x1 0, x2 0, x3 0, s1 0, s2 0, s3 0The initial tableau is:
BVs1
s2
P
�P001
x 1
13
�2
x 2
12
�3
x 3
11
�1
s1
100
s2
010
RHS
5010
0�
x 1 0, x 2 0, x 3 0, s1 0, s2 0
P � 2x 1 � 3x 2 � x 3
x 1 � x 2 � x 3 � s1 � 503x 1 � 2x 2 � x 3 �s2 � 10
BVs1
s2
s3
P
�P0001
x 1
2.20.8
1�3
x 2
�1.81.2
1�5
s1
1000
s2
0100
s3
0010
RHS
52.50.1
0�
x 1 � 0, x 2 � 0, x 3 � 0s1 � 0, s2 � 0, s3 � 0
P � 3 x 1 � 5x 2 � 02.2x 1 � 1.8x 2 � s1 � 50.8x 1 � 1.2x 2 � s2 � 2.5
x 1 � x 2 � s3 � 0.1
BVs1
s2
s3
P
�P0001
x 1
561
�2
x 2
�211
�1
x 3
144
�3
s1
1000
s2
0100
s3
0010
RHS202416
0�
x 1 � x 2 � x 3 � 6�2x 1 � 3x 2 � 12x 3 � 2x 1 0, x 2 0, x 3 0
25. Maximize P � x1 � 2x2 � 5x3
Subject to the constraintsx1 � 2x2 � 3x3 � 10
�3x1 � x2 � x3 � 12x1 0, x2 0 x3 0
System with slack variables:P � x1 � 2x2 � 5x3 � 10
x1 � 2x2 � 3x3 � s1 � 10�3x1 � x2 � x3 � s2 � 12
x1 0, x2 0, x3 0, s1 0, s2 0
Initial tableau:
27. Maximize P � 2x1 � 3x2 � x3 � 6x4
Subject to the constraints�x1 � x2 � 2x3 � x4 � 10�x1 � x2 � x3 � x4 � 8
x1 � x2 � x3 � x4 � 9x1 0, x2 0, x3 0, x4 0
System with slack variablesP � 2x1 � 3x2 � x3 � 6x4 � 10
� x1 � x2 � 2x3 � x4 � s1 � 10� x1 � x2 � x3 � x4 � s2 � 18
x1 � x2 � x3 � x4 � s3 � 19x1 0, x2 0, x3 0, x4 0s1 0, s2 0, s3 0
29. New tableau:
New system:
Current values: P � 300, x 2 � 150, s2 � 180
x 2 � �12 x 1 � 1
2s1 � 150s2 � �2x 1 � s1 � 180P � �s1 � 300
BVx 2
s2
P
�P001
x 112
20
x 2
100
s112
�11
s2
010
RHS150180300
�
BVs1
s2
s3
P
�P0001
x 1
�1�1
1�2
x 2
111
�3
x 3
2�1
1�1
x 4
111
�6
s1
1000
s2
0100
s3
0010
RHS
10890�
BVs1
s2
P
�P001
x 1
1�3�1
x 2
�2�1�2
x 3
�31
�5
s1
100
s2
010
RHS
1012
0�
BVs1
s2
s3
P
�P0001
x 1
312
�3
x 2
�11
�1�4
x 3
401
�2
s1
1000
s2
0100
s3
0010
RHS5560�
CHAPTER 4 Linear Programming: Simplex Method
AN-22 Answers to Odd-Numbered Problems
31. New tableau:
New system:
Current values:
33. New tableau:
New system: s1 � 3x1 � x3 � 20x4 � �2x1 � s2 � 24s3 � 3x2 � x3 � 28s4 � 2x1 � 2x3 � s2
P � �7x1 � 2x2 � 3x3 � 4s2 � 96
Current values: P � 96, s1 � 20, x4 � 24, s3 � 28,s4 � 0
Exercise 4.2 (p. 224)
1. (b); the pivot element is 1 in row 1, column 2
3. (a); the solution is P � , x1 � , x2 � 0 5. (c)
7. (b); the pivot element is 1 in row 3, column 4
9. The maximum is P � � when x1 � , x2 � .
11. The maximum is P � 8 when x1 � , x2 � .
13. The maximum is P � 6 when x1 � 2, x2 � 0.
15. There is no maximum for P; the feasible region is unbounded.
17. The maximum is P � 30 when x1 � 0, x2 � 0, x3 � 10.
19. The maximum is P � 42 when x1 � 1, x2 � 10, x3 � 0, x4 � 0.
21. The maximum is P � 40 when x1 � 20, x2 � 0, x3 � 0.
23. The maximum is P � 50 when x1 � 0, x2 � 15, x3 � 5, x4 � 0.
25. The maximum profit is $1500 when the manufacturer makes400 of Jean I, 0 of Jean II, and 50 of Jean III.
27. The maximum profit is $190 from the sale of 0 of product A,40 of product B, and 75 of product C.
23
23
127
247291
7204
7
327
2567
BVs1
x 4
s3
s4
P
�P00001
x 1
�320
�27
x 2
00
�3�3�2
x 3
1010
�3
x 4
01000
s1
10000
s2
010
�14
s3
00100
s4
00010
RHS202428
096�
P � 272 , s1 � 6, s2 � 55
2 , x 3 � 92
s1 � 2x 1 � s3 � 6
s2 � �54x 1 � 3
2x 2 � 14s3 � 55
2
x 3 � �34x 1 � 1
2x 2 � 14s3 � 9
2
P � �54x 1 � 1
2x 2 � 34s3 � 27
2
BV
s1
s2
x 3
P
�P
0
0
0
1
x 1
�2543454
x 2
0
�3212
�12
x 3
0
0
1
0
s1
1
0
0
0
s2
0
1
0
0
s3
�1
�141434
RHS
655292
272
�29. The maximum revenue is $275,000 when 200,000 gal of
regular, 0 gal of premium, and 25,000 gal of super premiumare mixed.
31. The maximum return is $7830 when she invests $45,000 instocks, $31,500 in corporate bonds, and $13,500 in munici-pal bonds.
33. The maximum profit is $14,400 when 180 acres of crop A,20 acres of crop B, and 0 acres of crop C are planted.
35. The maximum revenue is $2800 for 50 cans of can I, no cansof can II, and 70 cans of can III.
37. The maximum profit is $12,000 from 1200 television cabinetsand no stereo or radio cabinets.
39. The maximum profit is $30,000 when no TV are shippedfrom Chicago, 375 TVs are shipped from New York, and noTVs are shipped from Denver.
Section 4.3 (p. 236)
1. Standard form 3. Not in standard form
5. Not in standard form
7. Maximize P � 2y1 � 6y2
subject to y1 � 2y2 � 2y1 � 3y2 � 3y1 0 y2 0
9. Maximize P � 5y1 � 4y2
subject to y1 � 2y2 � 3y1 � y2 � 1y1 � 1y1 0 y2 0
11. Maximize P � 2y1 � 6y2
subject to y1 � 3y2 � 3y1 � 3y2 � 4y1 0 y2 0
13. The minimum is C � 6 when x1 � 0, x2 � 2
15. The minimum is C � 12 when x1 � 0, x2 � 4
17. The minimum is C � when x1 � , x2 � 0, x3 �
19. The minimum is C � 5 when x1 � 1, x2 � 1, x3 � 0, x4 � 0
21. Mr. Jones minimizes his cost at $0.22 when he adds 2 of pillP and 4 of pill Q to his diet.
23. Argus Company has a minimum cost of $290 by producing20 units of A, 30 units of B and 150 units of C.
25. Mrs. Mintz minimizes her cost at $65.20 by purchasing 4 ofLunch #1, 3 of Lunch #2, and 2 of Lunch #3.
135
85
215
Chapter 4 Review Exercises AN-23
Section 4.4 (p. 250)
1. The maximum is P � 44 when x1 � 4, x2 � 8
3. The maximum is P � 27 when x1 � 9, x2 � 0, x3 � 0
5. The maximum is P � 7 when x1 � 1, x2 � 2
7. x1 � 0, x2 � 0, x3 � , z �
9. M1 : A1 : 100, M2 : A1 : 400, M1 : A2 : 300, M2 : A2 : 0,C � $150,000
11. xI � , xII � , xIII � 0, C � $7.50
13. Ship 55 sets from the first warehouse to the first retailer, and75 sets from the second to the second, for a minimum costof $965.
15. The company should send 10 representatives from New Yorkand 5 from San Francisco to Dallas and any combination ofrepresentatives to Chicago (10 from SF; 0 from NY, or 9 fromSF, 1 from NY or 8 from SF, 2 from NY) for a minimum costof $6300.
254
58
203
203
CHAPTER 4 Review
True–False Items
1. T 2. F 3. T 4. F 5. T 6. F
Fill in the Blanks
1. Slack variables 2. column 3.
4. Van Neuman Duality Principle
Review Exercises
1. In standard form
3. In standard form
5. Not in standard form
7. Not in standard form
9.
11.
13. BVs1
s2
P
�P001
x 1
14
�1
x 2
31
�2
x 3
11
�1
x 4
26
�4
s1
100
s2
010
RHS
2080
0�
BVs1
s2
s3
P
�P0001
x 1
151
�6
x 2
531
�3
s1
1000
s2
0100
s3
0010
RHS200450120
0�
BVs1
s2
s3
P
�P0001
x 1
212
�2
x 2
533
�1
x 3
113
�3
s1
1000
s2
0100
s3
0010
RHS100
80120
0�
15. (a) The pivot element 2 is found in row s2, column x2. Thenew tableau after pivoting is
BV P x1 x2 s1 s2 RHS
(b) The resulting system of equations is
x1 � 15 � 4s1 � s2
x2 � 5 � s1 � s2
P � 125 � s1 � s2
(c) The new tableau is final tableau. The solution is maxi-mum P � 125 when x1 � 15 and x2 � 5.
17. (a) The pivot element 1 is the found in row s2, column x3.The new tableau after pivoting is
BV P x1 x2 x3 s1 s2 RHS
(b) The resulting system of equations iss1 � 14 � x1 � 2x1 � s2
x3 � 4 � x2 � s2
P � 12 � 2x1 � 2x2 � 3s2
(c) The problem requires additional pivoting. The new pivot1 is found in row s1, column x1.
19. (a) The pivot element 0.5 is found in row s1, column x1.The tableau after pivoting is
BV P x1 x2 s1 s2 RHS
(b) The resulting system of equations isx1 � 2 � x2 � s1
s2 � 1 � 0.5x2 � s1
P � 5 � 0.5x2 � 5s1
(c) The new tableau is the final tableau. The maximum is P � 5 when x1 � 2 and x2 � 0.
21. (a) The pivot element 1 is found in row s3, column x1. Thetableau after pivoting is
BV P x1 x2 x3 s1 s2 s3 RHS
(b) The resulting system of equations iss1 � 10 � 4x3 � 6s2 � s3
x2 � 8 � 8x3 � 4s2 � s3
x1 � 3 � 3x3 � 5s2 � s3
P � 14 � 13x3 � 15s2 � 3s3
s1
x 2
x 1
P�
0001
0010
0100
483
13
1000
�6�4�5
�15
1113
1083
14�
x 1
s2
P �001
100
10.50.5
2�2
5
010
215�
S1
x 3
P�0
01
10
�2
212
010
100
113
144
12�
72
12
52
x 1
x 2
P�0
0
1
1
0
0
0
1
0
�4
1
1
�52
12
72
15
5
125�
AN-24 Answers to Odd-Numbered Problems
(c) No solution exists since in the pivot column (s2) all 3entries are negative.
23. The maximum is P � 22500 when x1 � 0, x2 � 100, x3 � 50
25. The maximum is P � 352 when x1 � 0, x2 � 6/5, x3 � 28/5
27. In standard form
29. Not in standard form, constraints are not written as greaterthan or equal to inequalities.
31. Not in standard form, constraints are not written as greaterthan or equal to inequalities.
33. Maximize P � 8y1 � 2y2 subject to the
constraints
y1 0 y2 0
35. Maximize P � 100y1 � 50y2 subjectto the constraints y1 � 2y2 � 5
y1 0 y2 0
37. Minimum is C � 7 when x1 � 3, x2 � 1
39. Minimum is C � 350 when x1 � 50, x2 � 50
y1 � y2 � 4y1 � 3
2y1 � y2 � 22y1 � y2 � 1
41. Maximum is P � 20 when x1 � 0, x2 � 4
43. Minimum is C � 6 when x1 � 6, x2 � 0
45. Maximum is P � 12,250 when x1 � 0, x2 � 5, x3 � 25
47. The brewer should brew no lite beer, 180 vats of regularbeer, and 30 vats of dark beer to attain a maximize profit of$4500.
49. The manufacturer should ship no cars to dealer D2 and 25cars to dealer 2 from warehouse 1, and ship 40 cars to dealer1 and none to dealer 2 from warehouse 2. The minimumcost is $10,150.
51. The farmer will realize a maximum profit of $5714.29 if 0acres of corn, 0 acres of wheat, and 142.85 acres of soy areplanted.
53. The pension fund should purchase 1071.4 shares of DukeEnergy, 666.67 shares of Eastman Kodak, 294.12 shares ofGeneral Motors, 158.73 shares of H.J. Hienz to attain a maxi-mum value of $3250.
AN-24 Answers to Odd-Numbered Problems
(b) The resulting system of equations iss1 � 10 � 4x3 � 6s2 � s3
x2 � 8 � 8x3 � 4s2 � s3
x1 � 3 � 3x3 � 5s2 � s3
P � 14 � 13x3 � 15s2 � 3s3
(c) No solution exists since in the pivot column (s2) all 3entries are negative.
23. The maximum is P � 22500 when x1 � 0, x2 � 100, x3 � 50
25. The maximum is P � 352 when x1 � 0, x2 � 6/5, x3 � 28/5
27. In standard form
29. Not in standard form, constraints are not written as greaterthan or equal to inequalities
31. Not in standard form, constrains are not written as greaterthan or equal to inequalities
33. Maximize P � 8y1 � 2y2 subject to the
constraints
y1 � 0 y2 � 0
35. Maximize P � 100y1 � 50y2 subjectto the constraints y1 � 2y2 � 5
y1 � 0 y2 � 0
y1 � y2 � 4y1 � 3
2y1 � y2 � 22y1 � y2 � 1
37. Manimum is C � 7 when x1 � 3, x2 � 1
39. Manimum is C � 350 when x1 � 50, x2 � 50
41. Maximum is P � 20 when x1 � 0, x2 � 4
43. Minimum is C � 6 when x1 � 6, x2 � 0
45. Maximum is P � 12,250 when x1 � 0, x2 � 5, x3 � 25
47. The brewer should brew no lite beer, 180 vats of regularbeer, and 30 vats of dark beer to attain a maximize profit of$4500.
49. The manufacturer should ship no cars to dealer D2 and 25cars to dealer 2 from warehouse 1, and ship 40 cars to dealer1 and more to dealer 2 from warehouse 2. The minimumcost is $10,150.
51. The farmer will realize a maximum profit of $5714.29 if 0acrses of corn, 0 acrses of wheat, and 142.85 acrses of soy areplanted.
53. The pension fund should purchase 1071.4 shares of DukeEnergy, 666.67 shares of Easteran Kodak, 294.12 shares ofgeneral motors 158.73 shares of H.J. Hieng to attain a maxi-mum value of $ 3250.
Exercise 5.1 (p. 267)
1. 60% 3. 110%
5. 6% 7. 0.25%
9. 0.25 11. 1.00
13. 0.065 15. 0.734
17. 150 19. 18
21. 105 23. 5%
25. 160% 27. 250
29. 333 31. $10
33. $45 35. $150
37. 10% 39. 33.3%
41. 13.3% 43. $1140
45. $1680 47. $1263.16; 10.52%
49. $2380.95; 9.52% 51. $489.00
53. 3 years14
10003
CHAPTER 5 Finance
55. Take the discounted loan at 9% per annum.
57. Take the simple interest loan at 6.3% per annum.
59. Choose the simple interest loan at 12.3%.
61. $995,000
63. $62.20 interest received; interest rate is 1.24%
65. $4.40 interest received; interest rate is 1.06%
Exercise 5.2 (p. 276)
1. $1127.27 3. $578.81
5. $826.74 7. $98.02
9. $466.20
11. (a) $1124.86 interest earned: $124.86(b) $1126.16 interest earned: $126.16(c) $1126.82 interest earned: $126.82(d) $1127.27 interest earned: $127.27
13. (a) $1126.49(b) $1195.62(c) $1268.99
Exercise 5.4 AN-25
15. (a) $4438.55 17. (a) 8.16%(b) $3940.16 (b) 4.07%
19. 26.0% 21. 11.5 years
23. Choose b. 25. $917.43; $841.68
27. 5.35% 29. 6.82%
31. 6 % compounded annually
33. 9% compounded monthly 35. $109,400
37. $656.07 39. $10,420
41. $29,137.83 43. $42,640.10
45. yes 47. $18,508.09
49. 3.67%; $8.246 trillion 51. $10,810.76
53. 9.1% 55. 15.3 years
57. $940.90 59. $858.73
61. 22.8 years 63. 11.2 years
Exercise 5.3 (p. 288)
1. $1593.74 3. $5073.00
5. $7867.22 7. $6977.00
9. $113,201.03 11. $147.05 per month
13. $1868.68 per quarter 15. $4119.18 per month
17. $200.46 per month 19. $2088.11 per year
21. $62,822.56 23. $9126.56
25. $524.04 per month
27. $22,192.08 per year
14
39. Projected tuition 2012-2013: $ 6361.34Projected tuition 2013-2014: $ 6685.13Projected tuition 2014-2015: $ 7025.41Projected tuition 2015-2016: $ 7383.00Monthly sinking fund payment: $ 521.29
Exercise 5.4 (p. 299)
1. $15,495.62 3. $856.60
5. $85,135.64 7. $229,100; $25,239.51
9. $470.73 per month 11. $1719.43 per month
13. $2008.18 per year 15. $25,906.15
17. The monthly payment for the 9% loan is $1342.71 and themonthly payment for the 8% loan is $1338.30. The monthlypayment for the 9% loan is larger. The total interest paid islarger for the 9% loan, $242,813 compared to $161,192. After10 years the equity from the 8% loan is larger, $89,695.33compared to $67,617.64.
19. $55.82 per month
21. (a) $1207.64(b) $36.24 per week
23. (a) $40,000 down payment(b) $160,000 amount of loan(c) $1287.40 per month(d) $303,464(e) 22 years, 4 months(f) $211,823.20
25. $332.79 per month
27. $474.01 per month; $4,752.48 in interest paid
29. 30 year: monthly payment — $966.37; total interest —$235,893.20 15 year: monthly payment — $1189.89; total interest —$102,180.20
31. about 4 years and 8 months
33. Monthly payments are reduced by $128.07. They willpay $38,420.63 less in interest.
35. 62 months; $50,870.77 in interest saved
Exercise 5.5 (p. 304)
1. (a) $2930(b) 14 payments(c) 36 payments(d) $584.62
3. (a) $2162 trout(b) 26 months
5. (a) A0 � 0, An � 1.02An�1 � 500(b) 80 quarters, or 20 years(c) $159,738
Sinking Fund Cumulative Accumulated TotalPayment $ Deposit $ Deposits Interest $
1 22,192.08 22,192.08 0 22,192.08
2 22,192.08 44,384.16 1775.37 46,159.53
3 22,192.08 66,576.24 5,468.13 72,044.37
4 22,192.08 88,768.32 11,231.68 100,000.00
29. $205,367.98
31. $16,555.75 per quarter
33. (a) $180,611.12 35. 34 years(b) $2395.33 semiannually
37. Projected cost (2007): $ 22,997.82Projected cost including tax: $ 25,125.11Monthly sinking fund payment: $ 495.78
AN-26 Answers to Odd-Numbered Problems
7. (a) A0 � 150000, An � An�1 � 899.33(b) $149,850.67
(c)
(d) After 4 years and 10 months (58 payments)(e) With the 360th payment (30 years) the loan is paid.(f) $173,758.80(g) a. A0 � 150000, An � An�1 � 999.33
b. $149,750.67
c.
d. After 3 years and 1 month (37 payments)e. With the 279th payment (23 yrs. 3 mos.) the loan is
paid.f. $128,167.43
Exercise 5.6 (p. 309)
1. The lease option is preferable.
3. Machine A is preferable.
5. $1086.46
7. $992.26
9. 4.38%
�1 � 0.0612 �
�1 � 0.0612 �
CHAPTER 5 Review
True–False Items (p. 311)
1. T 2. T 3. F 4. F
Fill in the Blanks (p. 311)
1. proceeds 2. present value 3. annuity 4. amortized
Review Exercises (p. 311)
1. 15 2. 350 5. 21 % 7. 80
9. 2200 11. Dan paid $19.80 in sales tax
13. $52.50 interest is charged. Dan must repay $552.50.
15. Warren must pay $19,736.84 to settle his debt.
37
17. $125.12
19. (c) The 10% per annum compounded monthly loan willcost Mike less.
21. $71.36 23. 5.95%
25. 5.87% compounded quarterly
27. The Corey’s should save $1619.25 per month.
29. (a) The Ostedt’s monthly payments are $2726.10.(b) They will pay $517,830 in interest(c) After 5 years their equity is $117,508.93
31. The monthly payments are $1,049.00. The equity after 10 years is $21,576.
33. Mr. Graff should pay $119,431.51 for the mine.
35. The investor should pay $108,003.49 for the well.
37. Mr. Jones will have saved $10,078.44.
39. Bill must deposit $37.98 every quarter.
41. The monthly payments are $141.22.
43. The effective rate of interest is 9.38%.
45. John will receive $1156.60 every 6 mos. for 15 years.
47. After 30 months there will be $2087.09 in the fund.
49. The student’s monthly payment is $330.74.
51. Purchasing the trucks is the better choice.
53. $9845.45
Mathematical Questions from Professional Exams
1. b 2. c
3. b 4. b
5. d 6. a
7. c
Answers to Odd-Numbered Problems AN-27
CHAPTER 6 Sets: Counting Techniques
Exercise 6.1 (p. 325)
1. true 3. false
5. false 7. true
9. true 11. {2, 3}
13. {1, 2, 3, 4, 5} 15. Ø
17. {a, b, d, e, f, q}
19. (a) {0, 1, 2, 3, 5, 7, 8}(b) {5}(c) {5}(d) {0, 1, 2, 3, 4, 6, 7, 8, 9}(e) {4, 6, 9}(f) {0, 1, 5, 7}(g) Ø(h) {5}
21. (a) {b, c, d, e, f, g}(b) {c}(c) {a, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z}(d) {a, b, d, e, f, g, h, i, j, k, l, m, n, o, p, q, r, s, t, u, v, w, x, y, z}
23. (a) (b)
(c) (d)
(e) (f)
(g) (h)
25. A � is the set of members of the board of directors of IBMwho are also customers of IBM.
27. A � D is the set of all customers and/or stockholders of IBM.
29. � D is the set of all members of the board of directors ofIBM who are not customers of IBM.
31. M � S is the set of all male students who smoke.
33. � is the set of sophomores, juniors, and seniors togeth-er with the female freshmen.
35. F � S � M is the set of male freshmen who smoke.
37. The subsets of {a, b, c} are Ø, {a}, {b}, {c}, {a, b}, {a, c}, {b, c},{a, b, c}.
Exercise 6.2 (p. 330)
1. c(A) � 6 3. c(A � B) � 3
5. c[(A � B) � A] � 6 7. c(A � B) � 5
9. c(A � B) � 2 11. c(A) � 10
13. 452 cars 15. c(A) � 24
17. c(A � B) � 34 19. c(A � ) � 15
21. c(A � B � C) � 54 23. c(A � B � C) � 3
25. (a) 536 voters are Catholic or Republican.(b) 317 voters are Catholic or over 54.(c) 134 voters are Democtratic below 34 or over 54.
27. (a) 259 were seniors.(b) 455 were women.(c) 227 were on the dean’s list.(d) 76 seniors were on the deans list.(e) 118 seniors were female.(f) 93 women were on the dean’s list.(g) 912 students were in the college.
29. (a) 40 cars had power steering and air conditioning.(b) 35 cars had automatic transmission and air.(c) 40 cars had neither power steering nor automatic trans-
mission.(d) 205 cars were sold in July.(e) 155 cars were sold with automatic transmission or air
conditioning or both.
B
FM
A
UA B
A ∩ B–
UA B
C
(A ∩ B) ∪ C– –
UA B
A ∩ (A ∪ B)
UA B
A ∪ (A ∩ B)
UA B
C
(A ∪ B) ∩ (A ∪ C)
UA B
C
A ∪ (B ∩ C)
UA B
A = (A ∩ B) ∪ (A ∩ B)–
UA B
B = (A ∩ B) ∪ (A ∩ B)–
31. 8; U
A B
RH +
B –
O+
O –
A–
AB+
AB–
B +A+
AN-28 Answers to Odd-Numbered Problems
33. 46 use only one of the three brands.
35. Ø, {a}, {b}, {c}, {d}, {a, b}, {a, c}, {a, d}, {b, c}, {b, d}, {c, d},{a, b, c}, {a, b, d}, {a, c, d}, {b, c, d}, {a, b, c, d}. There are 16subsets of {a, b, c, d}.
Exercise 6.3 (p. 335)
1. 8 routes 3. 24 models
5. 864 outfits 7. 67,600 license plates
9. 120 arrangements
11. 264 � 104 � 4,569,760,000 user names
13. 26 � 253 � 10 � 93 � 2,961,562,500 user names
15. 360 words without repeated letters; 1296 words
17. 5040 rankings
19. 410 � 215 � 235 � 34,359,738,368 � 3.436 � 1010 ways
21. (a) 6,760,000 different license plates(b) 3,407,040 license plates without repeated digits(c) 3,276,000 license plates with no repeated letters or digits
23. 16 distinguishable car types are produced.
25. 60 types of homes can be built.
27. 256 different numbers can be formed.
29. 125,000 different lock combinations are possible.
31. 8 different paths through the maze.
Exercise 6.4 (p. 342)
1. 60 3. 120
5. 90 7. 9
9. 28 11. 42
13. 40,320 15. 1
17. 56 19. 1
21. The ordered arrangements of length 3 formed from the let-ters a, b, c, d, and e are:
abc, abd, abe, acb, acd, ace, adb, adc, ade, aeb, aec, aed,bac, bad, bae, bca, bcd, bce, bda, bdc, bde, bea, bec, bed,cab, cad, cae, cba, cbd, cbe, cda, cdb, cde, cea, ceb, ced,dab, dac, dae, dba, dbc, dbe, dca, dcb, dce, dea, deb, dec,eab, eac, ead, eba, ebc, ebd, eca, ecb, ecd, eda, edb, edc
P(5, 3) � 60
23. 123, 124, 132, 134, 142, 143, 213, 214, 231, 234, 241, 242, 243,312, 314, 321, 324, 341, 342, 412, 413, 421, 423, 431, 432;P(4, 3) � 24
25. 16 two-letter codes 27. 8 three-digit numbers
29. 24 ways 31. 60 three-letter codes
33. 6720 ways
35. 18,278 companies can be on the NYSE.
37. 132,860 ways
39. (a) 720 arrangements.(b) 120 arrangements if S comes first.(c) 24 arrangements if S must come first and Y last.
41. 19,958,400 ways 43. 3,368,253,000 ways
45. 32,760 ways officers can be chosen.
Exercise 6.5 (p. 349)
1. 15 3. 21
5. 5 7. 28
9. abc, abd, abe, acd, ace, ade, bcd, bce, bde, cde; C(5, 3) � 10
11. 123, 124, 134, 234; C(4, 3) � 4
13. 35 ways 15. 2380 ways
17. 1140 ways 19. 56 8-bit strings
21. 33,649 23. 90,720 different arrangements
25. 27,720 ways 27. 336 different committees
29. 27,720 ways
31. � 1.157 � 1076
33. 1950 different collections
35. 1,217,566,350 ways to select.
37. 60 differents ways
39. 10,626 different samples
41. P(50,15) � 2.943 � 1024 different guesses.
43. P(10,4) � 5040 different 4 digit numbers (no repeated digits).
Section 6.6 (p. 357)
1. x5 � 5x 4y � 10x3y 2 � 10x 2 y 3 � xy 4 � y 5
3. x 3 � 9x 2 y � 27 � y 2 � 27y 3
5. 16x 4 � 32x 3y � 24x 2 y 2 � 8xy 3 � y 4
7. 10 9. 405
11. 256 different subsets 13. 1023 non-empty subsets
15. 512 subsets
17.
19. �126 �
� ��77� � �7
6�� � �86� � �9
6� � �66� � �7
6� � �86� � �9
6��10
7 � � �97� � �9
6� � ��87� � �8
6�� � �96�
100!22! � 13! � 10! � 5! � 16! � 17! � 17!
Chapter 6 Review Exercises AN-29
21.
True–False Items
1. true 2. true 3. false 4. false
5. true 6. false 7. false
Fill in the Blanks
1. disjoint 2. permutation
3. combination 4. Pascal
5. binomial coefficients 6. binomial theorem
7. 40
Review Exercises
1. �, � 3. none of these
5. none of these 7. �, �
9. �, � 11. �, �
13. �, � 15. �, �
17. (a) {3, 6, 8, 9} (b) {6} (c) B(d) B (e) Ø (f) {1, 2, 3, 5, 6, 7, 8, 9}
19. (a) (b)
(c) (d)
(e) (f)
� n � (n � 1)!
(k � 1)!((n � 1) � (k � 1))!� n � �n � 1
k � 1�
k � �nk� � k �
n!k!(n � k)!
�n � (n � 1)!
(k � 1)!(n � k)!
21.
23. The set of all states whose names begin with A or which endwith a vowel.
25. The set of all states whose names end with a vowel and lieeast of the Mississippi River.
27. The set of all states whose names start with an A or end witha vowel and which lie east of the Mississippi River.
29. c(A � B) � 3
31. (a) c(A � B) � 20(b) A and B are disjoint.
33. c(A � B) � 1; c(A � B) � 5
35. (a) 160 cars were sold in June.(b) 35 cars had only power steering.
37. {1}, {1, 2}, {1, 3}, {1, 2, 3} 39. 1
41. 210 43. 12
45. 20 47. 12
49. 9900 51. 45
53. 1 55. 35
57. 9 59. 10 ways
61. 6 ways 63. 72 different styles
65. 1024 different ways to answer
67. (a) 120 words(b) 20 words if order is not important.
69. (a) 525 different committees(b) 1715 different committees
71. 12,441,600 ways 73. 20,790 different committees
75. 240 ways 77. 24 ways
79. The speakers can be ordered 24 ways.
81. (a) 4845 samples will contain only good plums.(b) 5700 samples will contain 3 good plums and 1 rotten
plum.(c) 7805 samples will contain one or more rotten plums.
83. 360 words can be made.
85. 302, 400 words can be made.
87. x4 � 8x3 � 24x2 � 32x � 16
89. 560
UA B
UA B
A ∪ B–
UA B
(A ∩ B) ∪ B–
UA B
B ∩ A–
UA B
C
(A ∪ B) ∩ C
UA B
C
(A ∩ B) ∩ (C )
UB C
(B ∪ C)–––––––
AN-30 Answers to Odd-Numbered Problems
CHAPTER 7 Probability
Exercise 7.1 (p. 373)
1. The outcomes from tossing a coin are H (heads) and T(tails). The sample space is {HH, HT, TH, TT}.
3. The outcomes from tossing each coin are H (heads) and T (tails). The sample space is {HHH, HHT, HTH, HTT,THH, THT, TTH, TTT}.
5. The outcomes from tossing each coin are H (heads) and T (tails), and the outcomes from tossing a die are the numbers1, 2, 3, 4, 5, and 6. The sample space is {HH1, HT1, TH1,TT1, HH2, HT2, TH2, TT2, HH3, HT3, TH3, TT3, HH4,HT4, TH4, TT4, HH5, HT5, TH5, TT5, HH6, HT6, TH6,TT6}.
7. The sample space, S � {RA, RB, RC, GA, GB, GC} where R � Red and G � Green.
9. The sample space, S � {AA, AB, AC, BA, BB, BC, CA, CB,CC}
11. The sample space, S � {AA1, AB1, AC1, BA1, BB1, BC1,CA1, CB1, CC1, AA2, AB2, AC2, BA2, BB2, BC2, CA2, CB2,CC2, AA3, AB3, AC3, BA3, BB3, BC3, CA3, CB3, CC3, AA4,AB4, AC4, BA4, BB4, BC4, CA4, CB4, CC4}
13. The sample space, S � {RA1, RB1, RC1, GA1, GB1, GC1,RA2, RB2, RC2, GA2, GB2, GC2, RA3, RB3, RC3, GA3, GB3,GC3, RA4, RB4, RC4, GA4, GB4, GC4} where R � Red andG � Green.
15. c(S) 16 17. c(S) 216 19. c(S) 1326 21. c(S) 676
23. Valid assignments are: 1, 2, 3, 6
25. Assignment 2 should be used.
27. P(H) � , P(T) �
29. P(1) � , P(2) � , P(3) � , P(4) � , P(5) � ,
P(6) �
31. Define W: A white ball is picked. P(W) �
33. Define G: A green ball is picked. P(G) �
35. Define R: A red ball is picked. P(W � R) �
37. P( ) � 39. P(A) �
41. P(E) � 43. P(E) �
45. Define A: an ace is drawn; H: a heart is drawn. P(A � H) �
47. Define S: a spade is drawn. P(S) �
49. Define F: a picture card is drawn. P(F) �
51. Define E: a card with a number less than 6 is drawn. P(E) �
53. Define A: an ace is drawn. P(A) � 1213
513
313
14
152
16
19
118
1123G � R
823
723
323
19
29
19
29
19
29
14
34
55. Define H: A randomly selected person has health insurance.P(H) � 0.845
57. P(H) � 0.5, P(T) � 0.5, answers will vary but the resultsshould be fairly close to the actual probabilities.
59. P(H) � 0.75, P(T) � 0.25, answers will vary but the resultsshould be fairly close to the actual probabilities.
61. P(Red) � , P(Yellow) � , P(White) � , answers will varybut the results should be fairly close to the actual probabilities.
Exercise 7.2 (p. 384)
1. 0.84 3. 0.44 5. 24.0% 7. 60.1%
9. P(A) � 0.75 11. P(A � B) � 0.65
13. P(A � B) � 0.5 15. 17. 0.30 19. 0.2
21. (a) P(A � B) � 0.7 (c) P(B � ) � 0.2(b) P(A � ) � 0.3 (d) P( ) 0.3
23. (a) 0.68 (b) 0.58 (c) 0.32
25. (a) P(1 or 2) � 0.57 (e) P(0 or 1) � 0.29(b) P(1 or more) � 0.95 (f ) P(0) � 0.05(c) P(1, 2 or 3) � 0.83 (g) P(1, 2 or 3) � 0.78(d) P(3 or more) � 0.38 (h) P(2 or more) � 0.71
27. P(E) � 29. P(E) � 31. P(E) �
33. The odds for E: 3 to 2; The odds against E: 2 to 3
35. The odds for F: 3 to 1; The odds against F: 1 to 3
37. 1 to 5, 1 to 17, 2 to 7 39. 23 to 27 41. 11 to 4
Exercise 7.3 (p. 391)
1. Probability all 5 are defective � 2.83 � 10�4; probability atleast 2 are defective � 0.103.
3. (a) P(3H) � (b) P(0H) �
5. (a) Probability 3 sevens is 0.005.(b) Probability of at least 2 sums of 7 or 11 is 0.126.
7. Probability of a repeated digit is 0.940.
9. Probability of no repeated letters is 0.006.
11. Probability the lists match is .
13. Probability of least 2 of 6 people are born in the same monthis 0.777.
15. Probability at least 2 senators have the same birthday isalmost 1.
17. Probability L precedes E is .
19. Probability the word begins with L is .15
12
124
132
516
12
512
34
A � BBA
118
815
215
13
Chapter 7 Review Exercises AN-31
21. Probability both the Giants and Dodgers are in the playoffs is .
23. Probability the wild card is from the Central division is .
25. Probability of the given bridge hand is 0.005.
27. Probability no two passengers exit on the same floor is .
Exercise 7.4 (p. 399)
1. P(E) � 0.5 3. P(E�F) � 0.429 5. P(E � F) � 0.3
7. P( ) � 0.5 9. P(E�F) � 0.25, P(F�E) � 0.5
11. P(F) � 0.5 13. P(E � F) �
15. (a) P(E) � (b) P(F) � 17. P(C) � 0.69
19. P(C�A) � 0.9 21. P(C�B) � 0.2 23. P(E � F) � 0.1
25. P(F �E) � 0.2 27. P(E� ) � 0.667
29. Probability exactly 2 girls, given 1st child is a girl is .
31. P(4H) � ; Yes, if we know the 2nd throw is a head P(4H/H) � .
33. Probability of drawing a heart and then a red is ; the prob-ability of drawing a red and then a heart is .
35. Probability of drawing 1 white and 1 yellow ball is .
37. (a) Probability of drawing a red ace is .(b) Probability of drawing a red ace given an ace was drawn
is .(c) Probability of drawing a red ace given a red was drawn
is .
39. Probability family has more than 2 children given it has atleast one child is 0.625.
41. P(E) � 0.4 43. P(H) � 0.24 45. P(E � H) � 0.1
47. P(G � H) � 0.08 49. P(E �H) � 0.417
51. P(G�H) � 0.333 53. P(E �F) � 0.107, P(F �E) � 0.818
55. (a) P(M) � (e) P(A�M) �
(b) P(A) � (f ) P(F �A � E) �
(c) P(F � B) � (g) P(M � ) �
(d) P(F �E) � (h) P(F � ) �
57. P(E �F) �
59. Define E: Person is a Republican; F: a person voted for the
Democrat. P(E) � ; P(E �F) � .1120
34
223
117373E51
263
3831009B72
1009
213596
3331009
171724
7241009
113
12
126
15
25204
25204
18
116
12
F
23
12
413
E
105512
513
265 61. P(S) � 0.467 63. P(N �E) �
Exercise 7.5 (p. 409)
1. P(E � F) � 0.24 3. P(F) � 0.625
5. No, P(E � F) � � � P(E)P(F).
7. (a) P(E �F) � 0.2 (c) P(E � F) � 0.08(b) P(F �E) � 0.4 (d) P(E � F) � 0.52
9. P(E � F � G) �
11. P(E � F) � 0.5 No, P(E � F) � 0.1 � 0.06 � P(E)P(F).
13. No, P(E � F) � � � P(E)P(F).
15. (a) Yes, P(E � F) � � P(E)P(F).
(b) No, P(E � F) � � � P(E)P(F).
17. P(H) � 19. P(4) � 21. P(4) �
23. F(5 � 6) � 25. P[(4 � 5 � 6) � H] �
27. P(RRR) � , P(RRL) � , P(RLR) � , P(LRR) � ,
P(RLL) � , P(LRL) � , P(LLR) � , P(LLL) �
(a) P(E) � (b) P(F) � (c) P(G) � (d) P(H) �
29. P(E � F) � � P(E)P(F)
31. (a) Probability both children have heart disease is .(b) Probability neither child is diseased is .(c) Probability exactly 1 has disease is .
33. (a) P(3T) � (b) P(2H and 1T) �
35. (a) Probability all recover is 0.656.(b) Probability 2 recover is 0.049.(c) Probability at least 2 recover is 0.996.
37. (a) Probability both are red is .
(c) Probability one is red is .
39. (a) P(A�U) � (b) P(A� ) �
(c) No, P(U � A) � � � P(U)P(A).
(d) No, P(U � ) � � � P(U)P( ).
(e) No, P( � A) � � � P( )P(A).
(f ) No, P( � ) � � � P( )P( ).
41. (a) Probability both vote for the candidate is .
(b) Probability neither vote for the candidate is .
(c) Probability one votes for the candidate is .49
19
49
AU54599408
1728AU
U1033136
1168U
A34459408
1956A
653136
121
1103U8
65
1225
925
964
2764
38
116
916
14
12
12
212
14
212
112
212
212
112
112
212
112
14
13
56
16
12
524
14
14
14
16
4147
19
29
511
CHAPTER 7 Review
True–False Items (p. 413)
1. T 2. F 3. F 4. F
5. T 6. F 7. T 8. T
Fill in the Blanks (p. 413)
1. 2. 32 3. 1, 0 4. 0.8
5. in favor of 6. equally likely 7. mutually exclusive
12
AN-32 Answers to Odd-Numbered Problems
23. (a) P( ) � 0.70 (e) P( ) � 1(b) P( ) � 0.55 (f) P( ) � 0.25(c) P(E � F) � 0 (g) P( ) � 1(d) P(E � F) � 0.75 (h) P( ) � 0.25
25. P(E � P) �
27. (a) No, since P(0) � � P(1) � � P(2) � .(b) Outcome 0 has the highest probability.(c) P(F) �
29. P(5 � 7 � 9) � 31. 1 to 5
33. Probability Bears win is .
35. P(E � F) � � P(E)P(F)
37. Define E: A student fails mathematics, and F: A studentfails physics. (a) P(E �F) � 0.333; (b) P(F �E) � 0.237 (c) P(E � F) � 0.560
39. The probability is
41. Define E: A person has blue eyes, F: A person has browneyes, G: A person is left handed.
(a) P(E � G) � 0.025 (b) P(G) � 0.0625 (c) P(E �G) � 0.4
43. (a) P(F �E) �
(b) P(E �F) �(c) Let E � scored over 80% and F � took form A.
Yes, because P(E � F) � 0.08 � P(E)P(F).(d) Let E � scored over 80% and F � took form B.
Yes, because P(E � F) � 0.12 � P(E)P(F).
45. Probability at least one matched is
47. (a) Probability all are underweight is 0.0002(b) Probability 2 are underweight is 0.083(c) Probability at most 1 is underweight is 0.910
49. Probability all are born on different days is 0.017
51. P(E �F) � 0.2
53. (a) Probability misses the 1st and gets the next 3 is 0.1029(b) Probability misses 10 in a row is 0.0282
55. Probability the car is black is
Mathematical Questions from Professional Exams (p. 419)
1. b 2. e 3. b 4. d 5. c
6. d 7. b 8. a 9. c 10. b
14
2527
15
25
5216
316
713
512
964
38
18
12
12
E � FE � FE � FFE � FE
CHAPTER 8 Additional Probability Topics
Exercise 8.1 (p. 430)
1. P(E � A) � 0.4 3. P(E � B) � 0.2 5. P(E �C) � 0.7
7. P(E) � 0.31 9. P(A�E) � 11. P(C �E) �7
311231
13. P(B �E) � 15. P(E) � 0.024 17. P(E) � 0.016
19. P(A1 � E) � 0.5; P(A2 � E) � 0.5
21. P(A1 � E) � 0.375; P(A2 � E) � 0.375; P(A3 � E) � 0.25
1231
Review Exercises (p. 414)
1. S � {0, 1, 2, 3, 4, 5}
3. The outcomes for each child are boy (B) and girl (G). Thesample space is {BB, BG, GB, GG}.
5. P(penny) � , P(dime) � , P(quarter) �
7. P(1) � , P(2) � , P(3) � , P(4) � , P(5) � , P(6) �
9. (a) Let X � the number of girls in a family of 4 children
X P (X)
0 0.0625
1 0.25
2 0.375
3 0.25
4 0.0625
(b) (i) P(0) � 0.0625 (iii) P(1) � 0.25(ii) P(2) � 0.375 (iv) 1 � P(4) � 0.9375
11. (a) Let X � the number of tails observed on three tosses ofa coin
X P (X)
0
1
2
3
(b) (i) P(3) � (iii) P(2) �
(ii) P(0) � (iv) P(2 � 3) �
13. (a) Probability both are blue is .
(b) Probability 1 is blue is .
(c) Probability at least 1 is blue is .
15. (a) P(A � B) � 0.6 (c) P( ) � 0.4(b) P( ) � 0.7 (d) P( � ) � 0.8
17. (a) P(3) � (b) P(5) � (c) P(6) �
19. (a) P( ) � 0.35 (c) No, because P(E � F) � 0.3 � 0.(b) P(E � F) � 0.75
21. (a) P( ) � (b) P(F) � (c) P( ) � 1324F11
2412E
E
73400
23100
21100
BAAA � B
5591
4591
1091
12
18
38
18
18
38
38
18
18
14
18
18
14
18
25
13
415
Exercise 8.3 AN-33
23. P(A1 � E) � 8/9 � 0.276; P(A2 � E) � 20/29 � 0.690;P(A3 � E) � 0.034
25. P(A2 � E) � 0; P(A3 � E) � 0.065;P(A4 � E) � 0; P(A5 � E) � 2/31 � 0.065
27. P(UI � E) � � 0.333; P(UII � E) � � 0.2;
P(UIII � E) � � 0.467
29. P(M �CB) � 0.953
31. P(D �V) � 0.385; P(R �V) � 0.39; P(I �V) � 0.225
33. P(Rock � positive) � 0.385; P(Clay � positive) � 0.209;P(Sand � positive) � 0.405
35. P(R) � 0.466; P(N �R) � 0.343
37. The probability the nurse forgot is .
39. Probability a student majors in engineering given she isfemale is 0.217.
41. (a) Probability a person is diseased given is positive test 0.858.(b) Probability a patient has the disease given a positive test
is 0.503.(c) Probability a patient has the disease given two positive
tests is 0.961.
Exercise 8.2 (p. 439)
1. b(7, 4; .20) � 0.0287 3. b(15, 8; .30) � 0.0138
5. b(15, 10; ) � � 0.0916 7. 0.2969
9. b(3, 2; ) � 11. b(3, 0; ) �
13. b(5, 3; ) � 15. b(10, 6; .3) � 0.0368
17. b(12, 9; .8) � 0.2362
19. P(At least 5 successes) � 0.0580
21. b(8, 1; ) � 23. P(at least 5 tails) �
25. P(2H/at least 1H occurs) � 27. b(5, 2; ) �
29. (a) b(8, 1; .05) � 0.2793 (c) 1 � P(8, 0; .05) � 0.3366(b) b(8, 2; .05) � 0.0515 (d) P(Fewer than 3 defective) �
0.9942
31. b(6, 3; .5) � � 0.3125516
6253888
16
28255
93256
132
12
80243
23
125216
16
29
13
300332768
12
911
715
315
515
33. (a)
(b) P(Exactly 2 successes) �
(c) b �
35. P(At least 2 hits) � 0.9996
37. P(At least 10 correct) �
P(At least 12 correct) � 0.6482
39. b(8, 8; .60) � 0.0007 41. b(10, 4; .23) � 0.1225
43. (a) P(At least 5 correct) �(b) P(At least 5 correct) � 0.3446
45. (a) b(10, 4; .124) � 0.0224(b) b(10, 0; .124) � 0.2661(c) P(At most 5 are over 65) � 0.9995
47. k Actual Value of P(k)
0 0.0625
1 0.25
2 0.375
3 0.25
4 0.0625
49. b(8, 3; .5) � 0.21875
Exercise 8.3 (p. 449)
1. E � 1.2 3. E � 50,800 fans
5. Mary should pay 80 cents per game.
7. Dave should pay $1.67 to play.
9. The price exceeds the expected value by $0.75.
11. (a) E � $0.75 (b) No, the game is not fair.(c) To make the game fair, a player should lose $2.00 if 1 tail
is thrown.
13. It is not fair; the expected loss is $0.42.
15. The expected loss is 1.2 cents, so Sarah should not play.
764
3092048
54256�4, 2; 14�
54256
SF
S
S
F
S
F
S
F
S
S
F
S
F
F
FSFSFSFSFSFSFSF
34
14
34
14
34
14
34
14
34
14
34
14
34
14
34
14
34
14
34
14
34
14
34
14
34
14
34
14
34
14
AN-34 Answers to Odd-Numbered Problems
17. He should bet $7 to make game fair.
19. Management should choose the second location.
21. E � � 333 times 23. E � 10 light bulbs
25. E � 1 person to have an unfavorable reaction.
27. E � 2.734 tosses.
29. The airline should schedule aircraft A to maximize expectedprofit.
Exercise 8.4 (p. 456)
1. Expected number of customers is 9; optimal number of carsis 9 for an expected daily profit of $168.
3.
Group size 2 3 4 5 6 7
Expected 0.403 0.524 0.565 0.574 0.568 0.556Tests perSaved Component
The optimal group size is 5.
13
20006
5. (a) E(X) � $75,000 � 75000(.05x) � 500x where x is thenumber of divers hired.
(b) Hiring two divers maximizes the net gain.
7. The probability the message is correctly received is 0.9647.
Exercise 8.5 (p. 459)
1. P(X � 0) � ; P(X � 1) � ; P(X � 2) �
3. P(X � 0) � ; P(X � 1) � ; P(X � 2) � ; P(X � 3) �
5. P(X � 0) � ; P(X � 1) � ; P(X � 2) � ; P(X � 3) �
7. E(X) � 1.2
9. Actual probabilities: P(X � 1) � , P(X � 2) � ,P(X � 3) � , P(X � 4) � , P(X � 5) � ; P(X � 6) � .
11. P(0.1 � X � 0.3) � 0.2
13. P(X � 2) � 12
16
16
16
16
16
16
130
310
12
16
18
38
38
18
14
12
14
CHAPTER 8 Review Exercises
True–False Items (p. 461)
1. T 2. F 3. F 4. T 5. F 6. T
Fill in the Blanks (p. 461)
1. Bayes’ formula
2. independent; the same
3. expected value of the experiment
4. a real number
5. expected value
Review Exercises
1. P(E � A) � 0.82 3. P(E � B) � 0.10
5. P(A�E) � 0.9866 7. P(B�E) � 0.0134
9. P(E � A) � 0.5 11. P(E �B) � 0.4 13. P(E �C) � 0.3
15. P(E) � 0.43 17. P(A�E) � 0.4651
19. P(B�E) � 0.4651 21. P(C �E) � 0.0698
23. (a) P(E �G) � (e) P(F �G) �
(b) P(G �E) � (f) P(G �F) �
(c) P(H �E) � (g) P(H �F) �
(d) P(K �E) � (h) P(K �F) � 1342
1169
1742
2264
27
1223
313
913
25. P(C) � 0.163
27. (a) b(5, 0; .20) � 0.3277 (b) b(5, 3; .20) � 0.0512
29. (a) b(12, 12; ) � � 0
(b) (c) 793 to 1255
31. P(At least 3 11’s) � .0016
33. E � 1.5 35. E � $29.52
37. (a) 18 cents would be a fair price for a ticket.(b) Alice paid 56 cents extra for the eight tickets.
39. E � 9.75
41. (a) The expected profit is $713,500
43. E � � 83.33
45. The probability the code is correctly received is 0.9349.
47. (a) Probability pooled test is positive is 1 � (1 � p)30.The expected number of tests in a pooled sample isE � 31 � 30 (1 � p)30.
49. (a) X � {0, 1, 2, 3, 4, 5}(b) P(X � 0) � 0.5838; P(X � 1) � 0.3394;
P(X � 2) � 0.0702; P(X � 3) � 0.0064;P(X � 4) � 0.0003; P(X � 5) � 0
(c) E(X) � 0.5
5006
7932048
1212
12
Answers to Odd-Numbered Problems AN-35
CHAPTER 9 Statistics
Exercise 9.1 (p. 472)
1. discrete 3. continuous 5. continuous 7. discrete
9. discrete 11. continuous
13. A poll should be taken either door-to-door or by means ofthe telephone of a cross section of people from differentparts of the country.
15. 17. Answers will vary. All answers should include a methodto choose a sample in which each member of the populationhas an equal chance of being selected.
19. Answers will vary. 21. Answers will vary.
Exercise 9.2 (p. 478)
1. (a)
(b) Northeast has the highest median income.(c) South has the lowest median income.
3. (a)
0
5,000
10,000
15,000
20,000
25,000
30,000
North-east
Mid-west
South West
Fam
ilies
(in
th
ousa
nds
)
0
10,000
20,000
30,000
40,000
50,000
60,000
Med
ian
inco
me
North-east
Mid-west
South West
(b)
(d) The South has the most families.(e) The Northeast has the fewest families.
5. (a)
(b) Married couple families have the highest median income.(c) Female householder — no spouse families have the low-
est median income.
7. (a)
0
100,000
200,000
300,000
400,000
500,000
600,000
700,000
800,000
Hea
rt d
isea
se
Can
cer
Stro
ke
Res
pira
tory
dis
ease
s
Acc
iden
ts
Dia
bete
s
Alz
hei
mer
's
Kid
ney
failu
re
Sept
icem
ia
$0
$15,000
$30,000
$45,000
$60,000
Med
ian
inco
me
Married Femalehouseholder
Malehouseholder
West20.6%
Northeast18.5%
Midwest22.9%South
38.0%
(b)
Heart disease37%
Cancer29%
Stroke9%
Respiratory diseases10%
Accidents5%
Diabetes4%
Alzheimer's3%
Kidney failure2% Septicemia
2%
(d) Heart disease was the leading cause of death in 2000.
9. (a) Sky West had the highest percentage of on-time flights.(b) Atlantic Coast had the lowest percentage of on-time
flights.(c) 84.3% of United Airline’s flights were on time.
11. (a) Housing, fuel and utilities are the largest component ofthe CPI.
(b) Miscellaneous goods and services from the smallestcomponent of the CPI.
Exercise 9.3 (p. 491)
1. (a)
25 30 35 40 45 50 550
1
2
3
4
5
6
7
8
9
Freq
uen
cy f
Score
(b)
AN-36 Answers to Odd-Numbered Problems
(c) Class Freq Class Freq Class Freq Class Freq
24 – 25.9 1 32 – 33.9 3 40 – 41.9 6 48 – 49.9 4
26 – 27.9 1 34 – 35.9 3 42 – 43.9 4 50 – 51.9 2
28 – 29.9 2 36 – 37.9 6 44 – 45.9 3 52 – 53.9 5
30 – 31.9 5 38 – 39.9 2 46 – 47.9 3 54 – 55.9 3
Score Freq Score Freq Score Freq Score Freq Score Freq Score Freq
25 1 31 2 36 2 41 5 46 2 51 1
26 1 32 1 37 4 42 3 47 1 52 3
28 1 33 2 38 1 43 1 48 3 53 2
29 1 34 2 39 1 44 2 49 1 54 2
30 3 35 1 40 1 45 1 50 1 55 1
Exercise 9.3 AN-37
(d) (e)
0
2
4
6
Freq
uen
cy
Score
24–
25.9
26–
27.9
28–
29.9
30–
31.9
32–
33.9
34–
35.9
36–
37.9
38–
39.9
40–
41.9
42–
43.9
44–
45.9
46–
47.9
48–
49.9
50–
51.9
52–
53.9
54–
55.9
0
2
4
6
Freq
uen
cy
Score
24–
25.9
26–
27.9
28–
29.9
30–
31.9
32–
33.9
34–
35.9
36–
37.9
38–
39.9
40–
41.9
42–
43.9
44–
45.9
46–
47.9
48–
49.9
50–
51.9
52–
53.9
54–
55.9
(f)
(g)
0
5
10
15
20
25
30
35
40
45
50
55
Cu
mu
lati
ve fr
equ
ency
24 26 28 30 32 34 36 38 40 42 44 46 48 50 52 54 56
Score
Cumulative Cumulative Cumulative CumulativeClass Freq Class Freq Class Freq Class Freq
24 – 25.9 1 32 – 33.9 12 40 – 41.9 29 48 – 49.9 43
26 – 27.9 2 34 – 35.9 15 42 – 43.9 33 50 – 51.9 45
28 – 29.9 4 36 – 37.9 21 44 – 45.9 36 52 – 53.9 50
30 – 31.9 9 38 – 39.9 23 46 – 47.9 39 54 – 55.9 53
3. (a) Class Freq Class Freq Class Freq Class Freq
50 – 54.9 1 70 – 74.9 8 90 – 94.9 12 110 – 115.9 0
55 – 59.9 6 75 – 79.9 11 95 – 99.9 2 115 – 119.9 2
60 – 64.9 3 80 – 84.9 2 100 – 104.9 2
65 – 69.9 6 85 – 89.9 12 105 – 109.9 4
(d)
AN-38 Answers to Odd-Numbered Problems
0
5
10
50–
54.9
55–
59.9
60–
64.9
65–
69.9
70–
74.9
75–
79.9
80–
84.9
85–
89.9
90–
94.9
95–
99.9
100–
104.
9
105–
109.
9
110–
114.
9
115–
119.
9
Weight
Freq
uen
cy
(b) (c)
0
5
10
50–
54.9
55–
59.9
60–
64.9
65–
69.9
70–
74.9
75–
79.9
80–
84.9
85–
89.9
90–
94.9
95–
99.9
100–
104.
9
105–
109.
9
110–
114.
9
115–
119.
9
Weight
Freq
uen
cy
(e)
0
15
30
45
60
75
505050 55 60 65 70 75 80 85 90 95 100
105
110
115
120
Weight
Cu
mu
lati
ve fr
equ
ency
Cumulative Cumulative Cumulative CumulativeClass Freq Class Freq Class Freq Class Freq
50 – 54.9 1 70 – 74.9 24 90 – 94.9 61 110 – 115.9 69
55 – 59.9 7 75 – 79.9 35 95 – 99.9 63 115 – 119.9 71
60 – 64.9 10 80 – 84.9 37 100 – 104.9 65
65 – 69.9 16 85 – 89.9 49 105 – 109.9 69
5. (a) There are 13 class intervals.(b) The lower class limit of the 1st class interval is 20 years, the
upper class limit is 24 years.
(c) The class width is 5 years.(d) There are 1,300,000 drivers between the ages of 70 and 84.(e) The interval 30 – 34 years has the most drivers.(f) The interval 80 – 84 years has the fewest drivers.( g )
20–
24
25–
2930
–34
35–
39
40–
44
45–
4950
–54
55–
5960
–64
65–
69
70–
74
75–
7980
–84
400,000
200,000
0
600,000
800,000
1,000,000
1,200,000
1,400,000
Age
Nu
mbe
r of
lice
nse
d dr
iver
s
Exercise 9.3 AN-39
7. Class Freq Class Freq Class Freq Class Freq
20 – 29 1,860,000 40 – 49 1,870,000 60 – 69 1,230,000 80 – 89 220,000
30 – 39 2,400,000 50 – 59 1,420,000 70 – 79 1,030,000
(a) There are 7 class intervals (b) The lower class limit for the last interval is 80 years, the upper class limit is 89 years.
0
250,000
500,000
750,000
1,000,000
1,250,000
1,500,000
1,750,000
2,000,000
2,250,000
2,500,000
Nu
mbe
r of
lice
nse
d dr
iver
s
20–
29
30–
39
40–
49
50–
59
60–
69
70–
79
80–
89
Age
(c) (d)
0
250,000
500,000
750,000
1,000,000
1,250,000
1,500,000
1,750,000
2,000,000
2,250,000
2,500,000
Nu
mbe
r of
lice
nse
d dr
iver
s
20–
29
30–
39
40–
49
50–
59
60–
69
70–
79
80–
89
Age
(e) Cumulative Cumulative Cumulative CumulativeClass Freq Class Freq Class Freq Class Freq
20 – 29 1,860,000 40 – 49 6,130,000 60 – 69 8,780,000 80 – 89 10,030,000
30– 39 4,260,000 50 – 59 7,500,000 70 – 79 9,810,000
(f)
0
1,050,000
2,100,000
3,150,000
4,200,000
5,250,000
6,300,000
7,350,000
8,400,000
9,450,000
10,500,000
Cu
mu
lati
ve n
um
ber
of li
cen
sed
driv
ers
20 30 40 50 60 70 80 90
Age
(c) The class width is 5 years.
0
50,000
100,000
150,000
200,000
250,000
300,000
350,000
400,000
450,000
Nu
mbe
r of
lice
nse
d dr
iver
s
20–
24
25–
29
30–3
4
35–
39
40–
44
45–
49
50–
54
55–
59
60–
64
65–
69
70–
74
75–
79
80–
84
Age
(d)
9. (a) There are 13 class intervals.(b) The lower class limit of the 1st class interval is 20 years,
the upper class limit is 24 years.
Class Freq Class Freq Class Freq Class Freq
11.0– 11.9 0 13.0– 13.9 5 15.0 – 15.4 2 17.0 – 17.4 1
12.0– 12.9 3 14.0– 14.9 6 16.0 – 16.9 3 18.0 – 18.9 0
AN-40 Answers to Odd-Numbered Problems
0
50,000
100,000
150,000
200,000
250,000
300,000
350,000
400,000
450,000
Nu
mbe
r of
lice
nse
d dr
iver
s
20–
24
25–
29
30–
34
35–
39
40–
44
45–
49
50–
54
55–
59
60–
64
65–
69
70–
74
75–
79
80–
84
Age
(e)
(f) Class interval 35 – 39 has the most licensed drivers.(g) Class interval 80 – 84 has the fewest licensed drivers.
11. (a) There are 15 class intervals.(b) The lower class limit for the first interval is 0, the upper
limit is $999.(c) The class width is $1000.
0
15
30
45
60
75
90
105
120
135
150
Nu
mbe
r of
4-y
ear
colle
ges
0–99
9
1000
–19
99
2000
–29
99
3000
–39
99
4000
–49
99
5000
–59
99
6000
–69
99
7000
–79
99
8000
–89
99
9000
–99
99
10,0
00–
10,9
99
11,0
00–
11,9
99
12,0
00–
12,9
99
13,0
00–
13,9
99
14,0
00–
14,9
99
Tuition (in dollars)
0
15
30
45
60
75
90
105
120
135
150N
um
ber
of 4
-yea
r co
llege
s
0–99
9
1000
–19
99
2000
–29
99
3000
–39
99
4000
–49
99
5000
–59
99
6000
–69
99
7000
–79
99
8000
–89
99
9000
–99
99
10,0
00–
10,9
99
11,0
00–
11,9
99
12,0
00–
12,9
99
13,0
00–
13,9
99
14,0
00–
14,9
99
Tuition (in dollars)
(d)
(e)
(f) Tuition between $8000 and $8999 occurs most frequently.
13. (a)
Exercise 9.4 AN-41
0
1
2
3
4
5
6
7
12.0
–12
.9
11.0
–11
.9
13.0
–13
.9
14.0
–14
.9
15.0
–15
.9
16.0
–16
.9
17.0
–17
.9
18.0
–18
.9
Birth rates per 1000 people
Freq
uen
cy
0
1
2
3
4
5
6
7
12.0
–12
.9
11.0
–11
.9
13.0
–13
.9
14.0
–14
.9
15.0
–15
.9
16.0
–16
.9
17.0
–17
.9
18.0
–18
.9
Birth rates per 1000 people
Freq
uen
cy
(b) (c)
Class Freq Class Freq Class Freq Class Freq
0 – 1.9 6 4 – 5.9 4 8 – 9.9 0 12 – 13.9 1
2 – 3.9 5 6 – 7.9 1 10 – 11.9 3
15. (a)
0
1
2
3
4
5
6
7
8
9
Freq
uen
cy
0–1.
9
2.0–
3.9
4.0–
5.9
6.0–
7.9
8.0–
9.9
10.0
–11
.9
12.0
–13
.9
Death rates (per 1000) from HIV related illness
(b)
0
1
2
3
4
5
6
7
8
9
Freq
uen
cy
0–1.
9
2.0–
3.9
4.0–
5.9
6.0–
7.9
8.0–
9.9
10.0
–11
.9
12.0
–13
.9
Death rates (per 1000) from HIV related illness
(c)
Exercise 9.4 (p. 502)
1. (a) mean: 31.25(b) median: 30.5(c) no mode
3. (a) mean: 70.4(b) median: 70(c) mode: 55
5. (a) mean: 78.8(b) median: 82(c) mode: 82
7. (a) mean: 73.33(b) median: 77.5(c) mode: 80
9. (a) mean: 31.29 years of age(b) median: 32 years of age(c) mode: 32 years of age
11. The mean cost per share is $109.40.
13. (a) The mean age of a new mother in 2000 was approxi-mately 27.668 years.
(b) The median age of a new mother in 2000 was approxi-mately 27.45 years.
25. (a)
AN-42 Answers to Odd-Numbered Problems
15. (a) The mean sales are approximately $119,966.(b) The median sales are approximately $120,000.
17. (a) The mean age of a licensed driver was approximately44.709 years.
(b) The median age of a licenced driver was approximately42.5 years.
19. The mean tuition in 1992 – 93 was approximately $8053.77.
21. (a) mean $41,300; median $36,000(b) The median describes the 4 clustered salaries well.
Exercise 9.5 (p. 511)
1. s � 7.058 3. s � 6 5. s � 13.946
7. mean: � 31.878; standard deviation: s � 7.921.
9. mean 885.333 hours, standard deviation 69.681 hours.
11. (a) Range: 17 years(b) s � 4.5548 years(c) � � 4.4807 years
13. (a) Population; we have all of the mothers represented.(b) The standard deviation is 6.367 years.
15. (a) Population data; all recorded earthquakes are included.(b) The mean magnitude of the earthquakes is 3.278.(c) The standard deviation of the magnitudes of the earth-
quakes recorded in 1998 is 1.382.
17. (a) s � 15.693285 years.(b) � � 15.693282 years.(c) Answers will vary.
19. (a) Population; all colleges of the kind are represented.(b) The standard deviation of the tuition is $3175.58.
21. (a) We expect at least 75% of the outcomes to be between 19and 31.
(b) We expect at least 64% of the outcomes to be between20 and 30.
(c) We expect at least 88.88% of the outcomes to be between16 and 34.
(d) We expect at most 25% of the outcomes to be less than19 or more than 31.
(e) We expect at most 11.11% of the outcomes to be lessthan 16 or greater than 34.
23. We expect at least 889 boxes to have between 0 and 12 defec-tive watches.
25. (a) Population(b) The mean number of births was 3,939,476.83.(c) The standard deviation of births was 58,187.82.(d) Exact; the data are not grouped.
Exercise 9.6 (p. 523)
1. � � 8, � � l
x
3. � � 18, � � l
5. (a) z � �0.66(b) z � �0.44(c) z � �0.01(d) z � 1.71(e) z � 2.57(f) z � 3
7. (a) A � 0.3133(b) A � 0.3642(c) A � 0.4989(d) A � 0.3888(e) A � 0.4893(f) A � 0.2734
9. A – 5.48%; B – 21.95%; C – 34.37%; D – 30.13%; F – 8.08%
11. A � 0.3085 13. A � 0.8181
15. (a) 1365 women are between 62 and 66 inches(b) 1909 women are between 60 and 68 inches(c) 1995 women are between 58 and 70 inches.(d) 3 women are taller than 70 inches.(e) 12 women are shorter than 59 inches.
17. (a) Approximately 1 student should weigh at least 142pounds.(b) We would expect 70% of the students to weigh between
124.61 and 135.39 pounds.
19. 57.05% of the clothing can be expected to last between 28and 42 months.
21. (a) Attendance lower than 10,525 will be in the lowest 70%of the figures.
(b) Approximately 77.46% of the attendance figures arebetween 8500 and 11,000 persons.
(c) Approximately 13.36% of the attendance figures differfrom the mean by at least 1500 persons.
23. Kathleen had the highest relative standing.
0.00
0.05
0.10
0.15
0.20
0.25
0.30
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Number of heads
Pro
babi
lity
Chapter 9 Review Exercises AN-43
CHAPTER 9 Review
True–False Items (p. 527)1. False 2. Truee 3. Falsee 4. Truee 5. False
Fill in the Blanks (p. 527)1. (a) mean (b) median (c) mode
2. the standard deviation
3. bell 4. Z-score
5. � � k; � � k
Review Exercises (p. 527)1. circumference, continuous
3. number of people, discrete
5. number of defective parts, discrete
7. Answers will vary. All answers should include a method tochoose a sample of 100 students from the population inwhich each student has an equal chance of being chosen.
9. Answers will vary. All answers should give examples of possi-ble bias.
–3 3
1
–1
(b) Answers vary.(c) mean 4.5, standard deviation 1.775
27. The approximate probability that there are between 285 and315 successes is 0.7372.
29. The approximate probability of obtaining 300 or more suc-cesses is 0.5.
31. The approximate probability of obtaining 325 or more suc-cesses is 0.0307.
33. (a) The approximate probability of having at least 80 but nomore than 90 hits is 0.2286.
(b) The approximate probability of having 85 or more hitsis 0.0918.
35. The approximate probability of selecting at least 10 unsealedpackages is 0.0116.
11. (a)
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Ride alone Car pool Ride bus Other
64%
5%
30%
1%
How Chicagoans get to work
Ride alone64%
Ride bus30%
Other1%
Car pool5%
How Chicagoans get to work(b)
37.
The graph assumes its maximum at x � 0.
39. P[X � 10] � 0.0311;
(b)
(c)
AN-44 Answers to Odd-Numbered Problems
(b)
15. (a) American Indian made up the smallest percentage of 4-year college enrollment.
(b) Asian-Americans were overrepresented in 4-year collegesin 1997.
(c) Approximately 533,820 Hispanic students were enrolledin 4-year colleges in 1997.
0
50
100
150
200
250
300
350
400
450
Freq
uen
cy
Do not like Like Like very much
Like36%
Do not like42%
Likevery much
22%
Score Frequency Score Frequency Score Frequency Score Frequency
21 2 62 1 74 1 87 2
33 1 63 2 75 1 89 1
41 2 66 2 77 1 90 2
42 1 68 1 78 2 91 1
44 1 69 1 80 4 92 1
48 1 70 2 82 1 95 1
52 2 71 1 83 1 99 1
55 1 72 2 85 2 100 2
60 1 73 2
0
1
2
3
4
20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100
Freq
uen
cy f
Test scores
0
5
10
Freq
uen
cy f
20–
29.9
30–
39.9
40–
49.9
50–
59.9
60–
69.9
70–
79.9
80–
89.9
90–
99.9
100–
109.
9
Test score
17. (a) High school diploma represents the highest level of edu-cational attainment of most Americans in 2000.
(b) Approximately 45,000,000 Americans have at least abachelor's degree.
(c) Approximately 32,000,000 Americans do not have a highschool diploma.
(d) Approximately 48,000,000 Americans have gone to col-lege but do not have a bachelor’s degree.
13. (a)
The range is 79.
19. (a)
Chapter 9 Review Exercises AN-45
(d)
0
5
10
Freq
uen
cy f
20–
29.9
30–
39.9
40–
49.9
50–
59.9
60–
69.9
70–
79.9
80–
89.9
90–
99.9
100–
109.
9
Test score
(e)
Cumulative Cumulative Cumulative CumulativeScore Frequency Score Frequency Score Frequency Score Frequency
21 2 62 13 74 27 87 41
33 3 63 15 75 28 89 42
41 5 66 17 77 29 90 44
42 6 68 18 78 31 91 45
44 7 69 19 80 35 92 46
48 8 70 21 82 36 95 47
52 10 71 22 83 37 99 48
55 11 72 24 85 39 100 5
60 12 73 26
(f)
0
10
20
30
40
50
Cu
mu
lati
ve fr
equ
ency
10 20 30 40 50 60 70 80 90 100 110
Test score
(b)
(c) (d)
AN-46 Answers to Odd-Numbered Problems
21. (a)
0
1
2
3
4
Freq
uen
cy f
4'12
"
4'16
"
4'22
"
4'30
"
4'36
"
4'39
"
4'40
"
4'46
"
4'50
"
4'52
"
4'56
"
5'01
"
5'02
"
5'06
"
5'08
"
5'12
"
5'18
"
5'20
"
5'31
"
5'37
"
5'40
"
5'43
"
5'48
"
5'50
"
5'55
"
6'01
"
6'02
"
6'10
"
6'12
"
6'30
"
6'37
"
6'40
"
7'15
"
7'05
"
Time
0
5
10
15
Freq
uen
cy
4'00
–4'
29"
4'30
–4'
59"
5'00
–5'
29"
5'30
–5'
59"
6'00
–6'
29"
6'30
–6'
59"
7'00
–7'
29"
Time
Class FrequencyInterval Fi
4�00–4�29 3
4�30 –4�59 10
5�00–5�29 11
5�30–5�59 9
6�00–6�29 4
6�30–6�59 3
7�00–7�29 2
Time Freq. Time Freq. Time Freq. Time Freq. Time Freq
4�12 1 4�46 2 5�08 1 5�43 1 6�12 1
4�15 1 4�50 1 5�12 2 5�48 1 6�30 1
4�22 1 4�52 1 5�18 1 5�50 1 6�32 1
4�30 2 4�56 1 5�20 3 5�55 1 6�40 1
4�36 1 5�01 1 5�31 2 6�01 1 7�05 1
439 1 5�02 1 5�37 1 6�02 1 7�15 1
4�40 1 5�06 2 5�40 2 6�10 1
The range is 3 minutes, 3 seconds.
Answers to Odd-Numbered Problems AN-47
(e)
0
5
10
15
Freq
uen
cy
4'00
–4'
29"
4'30
–4'
59"
5'00
–5'
29"
5'30
–5'
59"
6'00
–6'
29"
6'30
–6'
59"
7'00
–7'
29"
Time
Class CummulativeInterval Frequency
4�00–4�29 3
4�30 –4�59 13
5�00–5�29 24
5�30–5�59 33
6�00–6�29 37
6�30–6�59 40
7�00–7�29 42
(f)
(g)A
0
9
18
27
36
Cu
mu
lati
ve fr
equ
ency
4'00
"
4'30
"
5'00
"
5'30
"
6'00
"
6'30
"
7'00
"
7'30
"
Time
Age Freq Age Freq Age Freq Age Freq Age Freq
24 5 29 2 32 8 35 2 38 1
27 1 30 3 33 1 36 1 40 1
28 1 31 2 34 1 37 1 41 1
23. (a)
(b)
0
2
4
6
8
Freq
uen
cy f
24 28 32 36 40
Age
(d)
(e)
AN-48 Answers to Odd-Numbered Problems
Class Freq Class Freq Class Freq
20.0 – 24.9 5 30.0 – 34.9 15 40.0 – 44.9 2
25.0 – 29.9 4 35.0 – 39.9 5
0
3
6
9
12
15
18
Freq
uen
cy
20.0
–24
.9
25.0
–29
.9
30.0
–34
.9
35.0
–39
.9
40.0
–44
.9
Age
0
3
6
9
12
15
18
Freq
uen
cy
20.0
–24
.9
25.0
–29
.9
30.0
–34
.9
35.0
–39
.9
40.0
–44
.9
Age
Cumulative CumulativeClass Frequency Class Frequency
20.0 – 24.9 5 35.0 – 39.9 29
25.0 – 29.9 9 40.0–44.9 31
30.0 – 34.9 24
(g)
25. (a)
0
4
8
12
16
20
24
28
32
20 25 30 35 40 45
AgeC
um
ula
tive
freq
uen
cy
0%
10%
20%
30%
40%
50%
0–$1
2,00
0
$12,
000–
$46,
700
$46,
700–
$112
,850
$112
,850
–$1
71,9
50
$171
,950
–$3
07,0
60
over
$30
7,06
0
Income
Mar
gin
al t
ax r
ate
(c)
(f)
There are 5 class intervals.
Exercise 10.1 AN-49
(b)
0%
10%
20%
30%
40%
50%
0–$1
2,00
0
$12,
000–
$46,
700
$46,
700–
$112
,850
$112
,850
–$1
71,9
50
$171
,950
–$3
07,0
60
over
$30
7,06
0
Income
Mar
gin
al t
ax r
ate
27. (a) Mean: 5.7273 (b) Median: 5 (c) Mode: 0, 4, 8 and 10(d) Range: 12 (e) Standard deviation: 8.4853
29. (a) Mean: 16.2 (b) Median: 7 (c) Mode: 7(d) Range: 98 (e) Standard deviation: 29.5515
31. (a) Mean: 7 (b) Median: 7 (c) Mode: 7(d) Range: 11 (e) Standard deviation: 3.6515
37. (a) Answers may vary. We assume they are a sample of Joe’sscores calculating parts (b) and (c).
(b) Joe’s mean score is 75.57.(c) The standard deviation of Joe’s scores is 2.99.
39. (a) The approximate mean age of a male in 2000 was 37.8years.
(b) The approximate median age of a male in 2000 was41.069 years.
(c) The approximate standard deviation of the ages of malesin 2000 was 23.065 years.
41. We expect at least 75%, or 750 jars, to have between 11.9 and12.1 ounces of jam.
43. The probability a bag weighs less than 9.5 or more than 10.5pounds is less than 0.25.
45. z � �0.667
47. z � 1.4
49. z � 1.667
51. A � 0.0855
53. A � 0.7555
55. (a) 68.26% of the scores are between 20 and 30.(b) 2.28% of the scores are above 35.
57. 0.17% of the dogs will die before reaching the age of 10years, 4 months.
59. Bob scored equally well on both exams.
61. There is a probability of 0.9544 that this week’s productionwill lie between 30 and 50..
63. The probability of obtaining more than 160 positive resultsis approximately 0.001.
65. The probability that in a group of 200 test-takers between110 and 125 pass the test is 0.6893.
CHAPTER 10 Markov Chains; Games
Exercise 10.1 (p. 544)
1. (a) The entry represents the probability that an object instate 2 will move to state 1.
(b) v(1) � , v(2) �
(c) v(1) � , v(2) �
3. v(2) � 5. v(1) � [0.525 0.15 0.35]
7. a � 0.4, b � 0.1, c � 1 9. v(5) � [0.5040 0.4960]
11. (b) R C
P �
(c) P 2 � , P 3 � �0.742750.128625
0.257250.871375��0.815
0.09250.1850.9075�
RC
�0.900.05
0.100.95�
�157576
419576�
�1348
3548��14
34�
� 518
1318��13
23�
13. (b) 0 0 0 0 0 0 0
1 0 0 0 0 0 00 1 0 0 0 0 0
0 0 0 0 0 0P � 0 0 0 0 0 0
0 0 0 0 0 1 0 0 00 0 0 0 0 0 1 0 00 0 0 0 0 0 0 0 10 0 0 0 0 0 0 0 1
15. 57% of wine drinkers will be drinking wine X after 2 months.
17. v(10) � [0.3200 0.2892 0.1631 0.2277]
13
13
13
13
13
13
12
12
12
12
12
12
� �
AN-50 Answers to Odd-Numbered Problems
19. (a)
P �
(b) v(0) � [0 1 0 0 0 0](c) v(0)P(10) � [0 0.018752 0 0.012498 0 0.96875](d) Room 6
Exercise 10.2 (p. 555)
1. No, when you multiply row 2 by column 1 you will alwaysget a 0. So p21 � 0 for every power of P.
3. No, when you multiply row 1 by column 2 you will alwaysget a 0. So p12 � 0 for every power of P.
5. Yes, because P2 � , has all positive entries.
7. No, when you multiply row 3 by column 1 you will alwaysget a 0. So p31 � 0 for every power of P.
9. Yes, because P2 � , has all positive entries.
11. t � 13. t � 15. t �
A B C17. P �
� [0.30769 0.46154 0.23077] In the long run,the grocers’ stock is 30.8% brand A, 46.2% brand B, and23.1% brand C
19. The probability the grandson of a Laborite votes Socialist is 0.09. In the long run the membership distribution is[0.553 0.383 0.064].
21. (a) P �
(b) The probability is 44%.(c) The probability is 38.2%.(d) The distribution of grandchildren’s educational
attainment will be [0.538 0.383 0.079](e) The long run distribution will be [0.649 0.298 0.053]
23. t � [0.125 0.875] 25. t �
27. t � [0.268 0.209 0.021 0.318]
�4929
13�
�0.80.40.2
0.180.50.6
0.020.10.2 �
� 413
613
313�
ABC
�0.70.10.2
0.150.80.2
0.150.10.6 �
�1543
1243
1643��25
35��37
47�
�13135
1813
3163
16163
16
134813285
181348
5245
245
185
24
�
�7
3618
524
1336
3813
4912
1124
�
�12
0012
00
012
0000
0012
000
12
0012
00
012
0000
0012
011
�Exercise 10.3 (p. 565)
1. Yes, state 1 is an absorbing state. 3. No.
5. Yes, states 1 and 3 are absorbing states. 7. No.
9. No. 11. Yes, states 2 and 3 are absorbing states.
13. 15.
17.
19. (a) A person starting with $1.00 is expected to have $3.000.5 time. A person starting with $2.00 is expected tohave $3.00 one time.
(b) A player starting with $3.00 can expect to play 3 gamesbefore absorption.
21. The probability of accumulating $3.00 if he starts with $1.00is . The probabilities of accumulating $3.00 if he starts with$2.00 is .
23. (a) Colleen can expect to place 1.4 wagers before the gameends.
(b) The probability Colleen is wiped out is 0.84.(c) The probability Colleen wins the amount needed to buy
the car is 0.16.
25. (a) The expected number of wagers to be placed before thegame ends is 1.6.
(b) The probability Colleen is wiped out is 0.64.(c) The probability Colleen wins the amount needed to buy
the car is 0.36.
27. On the average a stock showing no change will remain 6.993days in that state.
29. I3 � ; S � ;
Q �
T � � , TS �
Exercise 10.4 (p. 570)
1. Katy’s game matrix is one twofinger fingers
.1 finger2 fingers
��11
1�1�
�0.45
0.45
0.75
0.55
0.55
0.25��
1.053
0
0
2
2
0
0.6
0.6
1��
2019
0
0
2
2
0
3535
1�
�0.0500
0.950.50
00.30 �
�000.75
00.20.25��1
00
010
001�
1019
419
�1012
00
0114
012
00012
0
00012
0
0014
012
��
1014
0
0114
0
001412
001412
��1013
0113
0013�
Chapter 10 Review Exercises AN-51
3. Katy’s game matrix is 1 4 7
5. The game is strictly determined; the value is �2.
7. The game is strictly determined; the value is 3.
9. The game is not strictly determined.
11. The game is strictly determined; the value is 2.
13. The game is not strictly determined.
15. The game is strictly determined if 0 a 3.
17. a � b � 0 for the game to be strictly determined.
Exercise 10.5 (p. 573)
1. E � $1.42 3. E(P,Q)’s 5. E(P,Q)’s 7. E(P,Q)’s
9. E(P,Q)’s 11. E(P,Q)’s 0
Exercise 10.6 (p. 580)
1. The optimal strategy for Player I is P � . The optimal
strategy for Player II is Q � . The expected payoff is
E � � 1.75.74
�1434�
�34 14�
13
179
198
94
147
��25
�8
5�811
�811
�14�3. The optimal strategy for Player I is P � . The optimal
strategy for Player II is Q � . The expected payoff is E � .
5. The optimal strategy for Player I is P � . The optimal
strategy for Player II is Q � . The expected payoff is E � .
7. The optimal strategy for the Democrat is to spend 37.5% ofthe time on domestic issues and 62.5% on foreign issues.The optimal strategy for the Republican is to spend 50% ofthe time on domestic issues and 50% of the time on foreignissues. The expected payoff is E � 1.5, so the Democrat gainsat least 1.5 units by employing the optimal strategy.
9. The optimal strategy for the spy is to try the deserted exit8.5% of the time and try the heavily used exit 91.5% of thetime. The optimal strategy for the spy’s opponent is to waitat the deserted exit 22.5% of the time and wait at the heavilyused exit 77.5% of the time. The expected payoff is E � �0.704, favoring the spy.
5071
78�5
838�
�58 38�
13�1
323�
�16 56�
CHAPTER 10 Review
Ture–False Items (p. 581)
1. F 2. F 3. F 4. T 5. T 6. T 7. T
Fill in the Blanks (p. 581)
1. 1 � m 2. nonnegative, one 3. v(k�1), v(0)
4. positive 5. payoff
Review Exercises (p. 582)
1. Not regular. 3. Not regular.
5. Yes, because P2 �
7. t � 9. t �
11. t � � [0.608 0.127 0.266]
13. (a) The situation froms a Markov chain because the shifts inmarket shares can be thought of as a sequence of experi-ments each of which results in one of a finite number ofstates.
�4879
1079
2179�
�3814
38��47
37�
�83
24059
1803
10
10724071
1803
10
5245
1825
�.
A B C
P �
(b) After one year, A will have 46.7% of the market, B willhave 28.3% of the market, and C will have 25% of themarket.
(c) After two years, A will have 47.2% of the market, B willhave 26.9% of the market, and C will have 25.9% of themarket.
(d) In the long run, A will have 47.3% of the market, B willhave 26.6% of the market, and C will have 26.0% of themarket.
15. (a) The salespersons movement among the universities canbe thought of as a sequence of experiments each ofwhich ends in one of a finite number of states.
(b) v(1) � �125
121
12�
P � U1
U2
U3�
U1
03434
U2
1014
U3
014
0�
ABC
�0.50.40.5
0.20.40.25
0.30.20.25�
AN-52 Answers to Odd-Numbered Problems
(c) In the long run, she should sell at U1 42.9% of the time,at U2 45.7% of the time, and at U3 11.4% of the time.
17. (a) The Markov chain is not absorbing.
19. (a) The Markov chain is absorbing.(b) The absorbing state is state 2.
(c) P �
21. (a) The Markov chain is not absorbing.
23. (a) The Markov chain is absorbing(b) The absorbing states are states 1 and 4.
(c)
25. (a)
P � �10.550000
000.55000
00.4500.5500
000.4500.550
0000.4500
00000.451
��
100.30.25
010.10.2
000.50.35
000.10.2�
�11314
0038
02338�
(b) Given that the man started with $2.00, on the averagethe process will be in state one 1.298 times; in state two2.361 times; in state three 1.412 times and in state four0.635 times.
(c) The expected length of the game is 5.71 bets.
(d) The probability the man loses all his money is 0.714;The probability he wins $5 is 0.286.
27. The game is not strictly determined.
29. The game is strictly determined; the value of the game is 9.
31. The game is strictly determined. The value of the game is 12.
33. E � 35. E � 1.75 37. E �
39. The optimal strategy for player I is P � . The optimal
strategy for player II is Q �
41. (a) The investor should invest in A 41.9% of the time andinvest in B 58.1% of the time.
(b) The percentage gain is 8.37%
43. The builder should use of the land for the shopping centerand of the land for the houses.1
3
23
�1212�
[12
12]
43
13
CHAPTER 11 Logic and Logic Circuits
Exercise 11.1 (p. 592)
1. Proposition
2. Not a proposition
5. Proposition
7. Proposition
9. A fox is not an animal.
11. I am not buying stocks.
13. Someone wants to buy my house.
15. Everybody has a car.
17. Either John is an economics major, or John is a sociologyminor (or both).
19. John is an economics major and a sociology minor.
21. Either John is not an economics major or John is not a soci-ology minor (or both).
23. Either John is not an economics major or John is a sociologyminor (or both).
Exercise 11.2 (p. 600)
1.
p q �q p � �q
T T F T
T F T T
F T F F
F F T T
3.
p q �p �q �p � �q
T T F F F
T F F T F
F T T F F
F F T T T
AN-52 Answers to Odd-Numbered Problems
(c) In the long run, she should sell at U1 42.9% of the time,at U2 45.7% of the time, and at U3 11.4% of the time.
17. (a) The Markov chain is not absorbing.
19. (a) The Markov chain is absorbing.(b) The absorbing state is state 2.
(c) P �
21. (a) The Markov chain is not absorbing.
23. (a) The Markov chain is absorbing(b) The absorbing states are states 1 and 4.
(c)
25. (a)
P � �10.550000
000.55000
00.4500.5500
000.4500.550
0000.4500
00000.451
��
100.30.25
010.10.2
000.50.35
000.10.2�
�11314
0038
02338�
(b) Given that the man started with $2.00, on the averagethe process will be in state one 1.298 times; in state two2.361 times; in state three 1.412 times and in state four0.635 times.
(c) The expected length of the game is 5.71 bets.
(d) The probability the man loses all his money is 0.714;The probability he wins $5 is 0.286.
27. The game is not strictly determined.
29. The game is strictly determined; the value of the game is 9.
31. The game is strictly determined. The value of the game is 12.
33. E � 35. E � 1.75 37. E �
39. The optimal strategy for player I is P � . The optimal
strategy for player II is Q �
41. (a) The investor should invest in A 41.9% of the time andinvest in B 58.1% of the time.
(b) The percentage gain is 8.37%
43. The builder should use of the land for the shopping centerand of the land for the houses.1
3
23
�1212�
[12
12]
43
13
CHAPTER 11 Logic and Logic Circuits
Exercise 11.1 (p. 592)
1. Proposition
2. Not a proposition
5. Proposition
7. Proposition
9. A fox is not an animal.
11. I am not buying stocks.
13. Someone wants to buy my house.
15. Everybody has a car.
17. Either John is an economics major, or John is a sociologyminor (or both).
19. John is an economics major and a sociology minor.
21. Either John is not an economics major or John is not a soci-ology minor (or both).
23. Either John is not an economics major or John is a sociologyminor (or both).
Exercise 11.2 (p. 600)
1.
p q �q p � �q
T T F T
T F T T
F T F F
F F T T
3.
p q �p �q �p � �q
T T F F F
T F F T F
F T T F F
F F T T T
Exercise 11.2 AN-53
5.
p q �p �p � q �(�p � q)
T T F F T
T F F F T
F T T T F
F F T F T
15.
p q r �q p � �q (p � �q)—� r
T T T F F T
T T F F F F
T F T T T F
T F F T T T
F T T F F T
F T F F F F
F F T T F T
F F F T F F
13.
p q �p �q p � q �p � �q (p � q) � (�p � �q)
T T F F T F T
T F F T F F F
F T T F F F F
F F T T F T T
11.
p q �q p—� q p � �q (p
—� q) � (p � �q)
T T F F F F
T F T T T T
F T F T F F
F F T F F F
17.
p p � p p � p
T T T
F F F
7.
p q �p �q �p � �q �(�p � �q)
T T F F F T
T F F T T F
F T T F T F
F F T T T F
9.
p q �q p � �q (p � �q) � p
T T F T T
T F T T T
F T F F F
F F T T F
19.
p q r p � q (p � q) � r q � r p � (q � r)
T T T T T T T
T T F T F F F
T F T F F F F
T F F F F F F
F T T F F T F
F T F F F F F
F F T F F F F
F F F F F F F
(p � q) (p � q) � r q � r p � (q � r)
T T T T
T T T T
T T T T
T T F T
T T T T
T T T T
F T T T
F F F F
AN-54 Answers to Odd-Numbered Problems
(ii) The negation of “Smith is an ex-convict and Smith isrehabilitated” is “Either Smith is not an ex-convict orsmith is not rehabilitated.”
35. (p � q) � r ≡ r � (p � q) (commutative property)≡ (r � p) � (r � q) (distributive property)≡ (p � s) � (q � s) (cummutative property)
39. Either Mike cannot hit the ball well or he cannot pitch strikes.
41. The baby is not crying and the baby is not talking all the time.
Exercise 11.3 (p. 606)
1. Converse: q Q �p; contrapositive: �q Q p; inverse: p Q �q
3. Converse: �p Q �q; contrapositive: p Q q; inverse: q Q p
5. Converse: If the grass is wet then it is raining.Contrapositive: If the grass is not wet then it is not raining.Inverse: If it is not raining then the grass is not wet.
7. Converse: If it is not cloudy then it is not raining.Contrapositive: If it is cloudy then it is raining. Inverse: If itis raining then it is cloudy.
9. Converse: If it is cloudy then it is raining. Contrapositive: Ifit is not cloudy then it is not raining. Inverse: If it is not rain-ing then it is not cloudy.
11. (a) If Jack studies psychology then Mary studies sociology.(b) If Mary studies sociology then Jack studies psychology.(c) If Jack does not study psychology then Mary studies
sociology.
31. The proposition “Smith is an ex-convict” is equivalent tothe proposition “Smith is an ex-convict and Smith is an ex-convict”; the proposition “Smith is an ex-convict” is equiva-lent to the proposition “Smith is an ex-convict or Smith is anex-convict”.
33. (i) The negation of “Smith is an ex-convict or Smith is reha-bilitated” is “Smith is not an ex-convict and Smith is notrehabilitated.”
21.
p q p � q p � q p � (p � q) p � (p � q)
T T T T T T
T F F T T T
F T F T F F
F F F F F F
23.
p q �q �q � q p � (�q � q)
T T F T T
T F T T T
F T F T F
F F T T F
(b) p Q (q � r) ≡ �p � (q � r) (hint)≡ (�p � q) � r (associative property)≡ �(p � �q) � r (DeMorgan’s property)≡ (p � �q) Q r (hint)
13. (a)
p q r �q q � r p Q (q � r) p � �q (p � �q) Q r
T T T F T T F T
T T F F T T F T
T F T T T T T T
T F F T F F T F
F T T F T T F T
F T F F T T F T
F F T T T T F T
F F F T F T F T
29.
(p � q) � [(p � q) �p q �p �q p � q �p � �q (�p � �q) (�p � �q)] � p
T T F F T F T T
T F F T F F F F
F T T F F F F F
F F T T F T T F
27.
p q �p q � �p p � (q � �p)
T T F F F
T F F F F
F T T T F
F F T F F
25.
p �p �(�p)
T F T
F T F
Exercise 11.5 AN-55
29. p Q q
31. �q � �p
33. q Q p
Exercise 11.4 (p. 612)
1. Let p and q be the statements, p: It is raining, q: John is goingto school. Assume that p Q �q and q are true statements.
Prove: �p is true.Direct: p Q �q is true.
Also, its contrapositive q Q �p is true and q is true.Then, �p is true by the law of detachment.
Indirect: Assume �p is false.Then p is true; p Q �q is true,Meaning, �q is true by the law of detachment.But q is true, and we have a contradiction.The assumption is false and �p is true.
3. Let p, q, and r be the statements, p: Smith is elected presi-dent; q: Kuntz is elected secretary; r: Brown is elected trea-surer. Assume that p Q q, q Q �r and p are true statements.
Prove: �r is true.Direct: p Q q and q Q �r are true.
So, p Q �r is true by the law of syllogism, and p is true.Thus �r is true by the law of detachment.
Indirect: Assume �r is false.Then r is true; p Q q is true; q Q �r is true.So, p Q �r is true by the law of syllogism.r Q �p, its contrapositive, is true.So, �p is true by the law of detachment.But p is true, and we have a contradiction.The assumption is false and �r is true.
5. Invalid. If the hypotheses p Q q and �p are both true, thenp is false. In the conditional, if p is false, q can be either trueor false. So the conclusion, �q, could be true or false.
7. Valid. Let p: Tami studies, q: Tami fails, and r: Tami playswith dolls often. We are given p Q �q and � r Q p and wemust show q Q r. Using the Law of the contrapositive wehave q Q �p and �p Q r. Then by the Law of Syllogism,q Q r.
Exercise 11.5 (p. 616)
1. The output is 1 when a) both p � 1 and q � 1 or b) both p � 0, and q � 0, or c) both p � 0, and r � 1.
27.
p q p � q p � (p � q) p � (p � q) ⇔ p
T T T T T
T F T T T
F T T F T
F F F F T
15.
p q �p p � q �p � (p � q)
T T F T T
T F F F F
F T T F T
F F T F T
17.
p q �p �p � q p � (�p � q)
T T F F T
T F F F T
F T T T T
F F T F F
25.
p � (q � r)p q r p � q q � r (p � q) � r p � (q � r) ⇔ (p � q) � r
T T T T T T T T
T T F T F F F T
T F T F F F F T
T F F F F F F T
F T T F T F F T
F T F F F F F T
F F T F F F F T
F F F F F F F T
23.
p q p Q q p � (p Q q)
T T T T
T F F F
F T T F
F F T F
21.
p �p �p � p
T F T
F T T
19.
p q �p �p Q q
T T F T
T F F T
F T T T
F F T F
AN-56 Answers to Odd-Numbered Problems
CHAPTER 11 Review
True–False Items (p. 617)
1. F 2. T 3. T4. F 5. T
Fill in the Blanks (p. 617)
1. p � q 2. �p3. logically equivalent 4. hypotheses; conclusion5. zero; one
CHAPTER 11 Review Questions (p. 617)
1. Proposition
3. Not a proposition
5. Proposition
7. Not a porposition
9. I go to the math learning center, or I complete my mathhomework.
3. The output is 1 when p and q are both 1.
5.
7.
9. (For Problem 1):
(For Problem 3):
(For Problem 5):
(For Problem 7):
11. The truth table and two possible diagrams for this circuit iseither
p q
1 1 1
1 0 0
0 1 0
0 0 1
pq
pq XOR
pq
p
q
r
XOR
p
q NOR
AND
p
q OR
OR
AND
or
p q
1 1 0
1 0 1
0 1 1
0 0 0
(a) and
(b)
13.
15. p � q ≡ �(�p �q)
(a)
(b)
pq ⊕ pr ⊕ q(�r) ≡ pqr ⊕ pq (�r) ⊕ pr ⊕ q(�r)≡ pr(q ⊕ 1) ⊕ (p ⊕ 1)[q(�r)]
17. Show pq ⊕ pr ⊕ q(�r) � pr ⊕ q(�r)pq ⊕ pr ⊕ q(�r) � pq(r ⊕ �r) ⊕ pr ⊕ q(�r)
� pqr ⊕ pq(�r) ⊕ pr ⊕ q(�r)� pqr ⊕ pr ⊕ pq(�r) ⊕ q(�r)� pr(q � 1) ⊕ q(�r)(p � 1)� pr(1) ⊕ q(�r)(1)� pr � q(�r)
p
q
NAND
NAND
NAND
pq NAND
p
pq XOR
pq XOR
Chapter 11 Review Exercises AN-57
11. If I go to the math learning center then I complete my mathhomework.
13. If I don’t go to the math learning center, then I don’t com-plete my math homework.
15. I don’t go to the math learning center, and I don’t completemy math homework.
17. Nobody is rich.
19. Either Danny is tall or Mary is not short.
21. (c)
23. (a)
25.
p q p � q �p (p � q) � �p
T T T F T
T F F F F
F T F T T
F F F T T
27.
p q p � q (p � q) � p
T T T T
T F T T
F T T F
F F F F
29. q Q p
31. p ⇔ q
33. Define the statements p: The temperature outside is below30°, q: I wear gloves.(a) p Q q(b) q Q p; If I wear gloves, then the temperature outside is
below 30°.(c) �q Q �p; If I do not wear gloves, then the temperature
outside is not below 30°.(d) �p Q �q; If the temperature is not below 30°, then I do
not wear gloves.
35. Define the statements p: Stu will work on the project, q: Juliehelps.(a) q Q p(b) p Q q; If Stu works on the project, then Julie helps.(c) �p Q �q; If Stu will not work on the project, then Julie
does not help.(d) �q Q �p; If Julie does not help, then Stu will not work
on the project.
37. Define the statements p: Kurt will go to the club, q: Jessicacomes to town.(a) q Q p(b) p Q q; If Kurt goes to the club, then Jessica comes to
town.(c) �p Q �q; If Kurt does not go to the club, then Jessica
does not come to town.(d) �q Q �p; If Jessica does not come to town, then Kurt
will not go to the club.
39. Define the statements p: Brian must come to the gym, q:Mike works out.(a) q Q p(b) p Q q; If Brian must come to the gym, then Mike works
out.(c) �p Q �q; If Brian must not come to the gym, then
Mike does not work out.(d) �q Q �p; If Mike does not work out, then Brian must
not come to the gym.
41. p: Patrick goes to practice; q: Patrick starts the game Show p Q q is equivalent to �p � q.
p q �p p Q q �p � q p Q q PQ (�� � q)
T T F T T T
T F F F F T
F T T T T T
F F T T T T
43. See table in problem 41 above
45. Define the statements p: I paint the house, q: I go bowling.Assume the premises �p Q q and �q are true. Show p is true.Direct Proof: Since �p Q q is true, its contrapositive �q Q p is true. When �q Q p and �q are true then by theLaw of Detachment, p is true, I paint the house.Indirect Proof: Assume the conclusion p is false. By the Lawof Contradiction �p is true. Since �p Q q and �p are true,by the Law of Detachment, q is true, but this is acontradiction. q is false. So the assumption that p is false isincorrect. p is true, I paint the house.
47. Define the statements p: John is in town, q: Mark gets tickets,and r: We go to the game. Assume the premises p Q q,�r Q �q, and p are true.Direct Proof: Since �r Q �q is true, its contrapositive,q Q r is true. Since p Q q and q Q r are true, p Q r is true,p Q r is true by Law of Syllogism. Finally, since p Q r and p aretrue, by the Law of Detachment, r is true. We went to the game.
49. Define the statements p: I pay a finance charge, q: Mypayment is late, r: Colleen sends the mail.Assume the premises q Q p, r � q, and �r are true. Prove pis true.
APPENDIX A Review
AN-58 Answers to Odd-Numbered Problems
Direct Proof: Since r � q is true provided at least one of itscomponents is true and r is false by the Law ofContradiction, q if true. By the Law of Detachment, since q Q p and q are true, so is p. I pay a late charge.
51. Define the statements p: Rob is a bad boy, q: Danny is crying,r: Laura is a good girl.Assume the premises p � q, r Q �p, and �q are true. Wewant to prove r (or �r).Direct Proof: p � q is true whenever at least one of its com-ponents is true. �q is true, and by the Law of Contradictionq is false. So p is true. Since r Q �p is true, its contraposi-tive, p Q �r, is true, and by the Law of Detachment �r istrue. Lara is not a good girl.
53. p �(pq)q
55.
57. (p ⊕ q)[�(pq)] � (p ⊕ q)(�p ⊕ �q)� p(�p) ⊕ p(�q) ⊕ q(�p) ⊕ q(�q)� 0 ⊕ p(�q) ⊕ q(�p) ⊕ 0� p(�q) ⊕ (�p)q
p
q
�(pq)
p�q
(p�q) [�(pq)]
p
q
Exercise Appendix A.1 (p. 635)
1. (a) 2 and 5 are natural numbers.(b) �6, 2, and 5 are integers.(c) �6, , �1.333 . . . , 2, and 5 are rational numbers.(d) π is an irrational number.(e) All the numbers are real numbers.
3. (a) 1 is a natural number.(b) 0 and 1 are integers.(c) All the numbers are rational numbers.(d) There are no irrational numbers in the set C.(e) All the numbers are real numbers.
5. (a) There are no natural numbers in the set E.(b) There are no integers in the set E.(c) There are no rational numbers in the set E.(d) All the numbers are irrational.(e) All the numbers are real numbers.
7. (a) 18.953 9. (a) 28.653(b) 18.952 (b) 28.653
11. (a) 0.063 13. (a) 9.999(b) 0.062 (b) 9.998
15. (a) 0.429 17. (a) 34.733(b) 0.428 (b) 34.733
19. 3 � 2 � 5 21. x � 2 � 3 � 4
23. 3y � 1 � 2 25. x � 2 � 6
27. � 6 29. 7 31. 6
33. 1 35. 37. �11133
x2
12
39. 11 41. �4 43. 1
45. 6 47. 49.
51. 53. 55.
57. � 59. 61.
63. 6x � 24 65. x2 � 4x
67. x2 � 6x � 8 69. x2 � x � 2
71. x2 � 10x � 16 73. x2 � 4
79. Subtraction is not commutative. Examples will vary.
81. Division is not associative. Examples will vary.
83. This is true by the symmetric property of real numbers.
85. All real numbers are either rational or irrational; no realnumber is both.
87. 0.99 . . . � 1
Exercise Appendix A.2 (p. 642)
1.
3. � 5. � 7. � 9. �
11. � 13. x � 0 15. x � 2 17. x � 1
19.
21.
23. 1 25. 2 27. 6 29. 4
–1 0 2 4
–2 20
–2.5 –1 0
0.25
134
52
1522
160
1645
1336
7930
2320
445
27
Exercise Appendix B AN-59
31. �28 33. 35. 0 37. 1
39. 5 41. 1 43. 22 45. 2
47. (c) x � 0 49. (a) x � 3 51. none
53. (b) x � 1, (c) x � 0, (d) x � �1
55. {x � x � 5} 57. {x � x � �4}
59. C � 0° 61. C � 25°
63. x � 2 65. x � 6
67. x � �1 69. x � �4
71. x � �3,
73. x �1,
75. x 1,
77. x � �4,
79. A � l � w; {
81. C � � d;
83. A � x2;
85. V � r3;
87. V � x3;
89. (a) $6,000(b) $8,000
91. (a) �113 � 115� � ��2� � 2 � 5(b) �109 � 115� � ��6� � 6 � 5
93. (a) Yes, �2.999 � 3� � ��0.001� � 0.001 � 0.01.(b) No, �2.89 � 3� � ��0.11� � 0.11 � 0.01.
95. No, is larger by 0.000333. . . .
97. No.
Exercise Appendix A.3 (p. 648)
1. 64 3. 5. 1
7. 4 9. 3 11. 2
13. 4 15. 17.14
164
18
13
{x � x � 0}, {V �V � 0}
{r � r � 0}, {V �V � 0} 43
{x � x � 0}, {A�A � 0} √34
{d �d � 0}, {C �C � 0}
l �l � 0}, {w � w � 0}, {A� A � 0}
–4 –2 20
–2 0 31
–1–3 0 2
–2–3–5 0 2
45 19. (a) 11.2116 21. (a) 8.8152
(b) 11.5873 (b) 8.8214(c) 11.6639 (c) 8.8244(d) 11.6648 (d) 8.8250
23. (a) 21.2166(b) 22.2167(c) 22.4404(d) 22.4592
25. 3 27. �1 29. 8
31. 33. 2 35. 3
37. x � log2 5 39. t � log1.1 10 41. 55.590
43. 1385.002 45. 1499.364 47. 12,432.323
49. 2074.642
Exercise Appendix A.4 (p. 653)
1. 1, 2, 3, 4, 5 3. , , , ,
5. 1, �4, 9, �16, 25 7. , , , ,
9. , , , , 11. , , , ,
13. 1, 3, 5, 7, 9 15. �2, �1, 1, 4, 8
17. 5, 10, 20, 40, 80 19. 3, 3, , ,
21. 1, 2, 2, 4, 8
23. A, A � d, A � 2d, A � 3d, A � 4d
25. , , , ,
27. (a) a1 � 2, r � 2 29. (a) a1 � , r �
(b) 2, 4, 8, 16 (b) , , ,
(c) 30 (c)
31. (a) a1 � , r � 2 33. (a) a1 � , r �
(b) , , 1, 2 (b) , , 2, 2
(c) (c) 2 � 3 �
35. (a) a1 � , r �
(b) , , ,
(c) 6516
2716
98
34
12
32
12
√3 4√3 2154
√3 2√3 4√3 212
14
√3 2√3 214
�4516
� 316�3
8�34�3
2
12�3
2
√2 � √2 � √2 � √2 � √2
√2 � √2 � √2 � √2√2 � √2 � √2√2 � √2√2
18
12
32
5e5
4e4
3e3
2e2
1e� 1
421
30� 120
112�1
6
861
841
27
25
12
56
45
34
23
12
13
APPENDIX B Using Lindo to Solve Linear Programming Problems
Exercise Appendix B (p. 659)
1. Maximum of P � 24 when x1 � 0, x2 � 12, and x3 � 0.
3. Maximum of P � 15 when x1 � 5, x2 � 0, and x3 � 0.
5. Maximum of P � 40 when x1 � 14, x2 � 0, and x3 � 4.
7. Maximum of P � 6 when x1 � 6, x2 � 0, and x3 � 0.
9. Maximum of P � 15.2 when x1 � 1.6, x2 � 4.8, and x3 � 2.4.
11. Maximum of P � 15 when x1 � 0, x2 � 5, and x3 � 0.
13. No maximum value.
AN-60 Appendix Answers
APPENDIX C Graphing Utilities
Exercise Appendix C.1 (p. 663)
1. (�1, 2) quadrant II 3. (3, 1) quadrant I
5. X min � �6 7. X min � �6X max � 6 X max � 6X scl � 2 X scl � 2Y min � �4 Y min � �1Y max � 4 Y max � 3Y scl � 2 Y scl � 1
9. X min � 3 11. X min � �12X max � 9 X max � 6X scl � 1 X scl � 1Y min � 2 Y min � �4Y max � 10 Y max � 8Y scl � 2 Y scl � 1
15. Maximum of P � 30 when x1 � 0, x2 � 0, and x3 � 10.
17. Maximum of P � 42 when x1 � 1, x2 � 10, x3 � 0, and x4 � 0.
19. Maximum of P � 40 when x1 � 20, x2 � 0, and x3 � 0.
21. Maximum of P � 50 when x1 � 0, x2 � 15, x3 � 5, and x4 � 0.
23. Minimum of P � 76.25 when x1 � 6.25, x2 � 0, x3 � 0, x4 �20, x5 � 0, x6 � 50, and x7 � 0.
13. X min � �30 15. X min � �10X max � 50 X max � 110X scl � 10 X scl � 10Y min � �100 Y min � �20Y max � 50 Y max � 180Y scl � 10 Y scl � 20
Exercise Appendix C.2
1. (a) (b) (c) (d)
3. (a) (b) (c) (d)
5. (a) (b) (c) (d)
– 5 5
20
– 20
–10 10
8
– 8
–10 10
8
– 8
– 5 5
4
– 4
– 5 5
20
– 20
–10 10
8
– 8
–10 10
8
– 8
– 5 5
4
– 4
– 5 5
20
– 20
–10 10
8
– 8
–10 10
8
– 8
– 5 5
4
– 4
Exercise Appendix C-2 AN-61
7. (a) (b) (c) (d)
9. (a) (b) (c) (d)
11. (a) (b) (c) (d)
13. (a) (b) (c) (d)
15. (a) (b) (c) (d)
17. 19. 21. 23.
– 5 5
20
– 20
–10 10
8
– 8
–10 10
8
– 8
– 5 5
4
– 4
– 5 5
20
– 20
–10 10
8
– 8
–10 10
8
– 8
– 5 5
4
– 4
– 5 5
20
– 20
–10 10
8
– 8
–10 10
8
– 8
– 5 5
4
– 4
– 5 5
20
– 20
–10 10
8
– 8
–10 10
8
– 8
5 5
4
– 4
– 5 5
20
– 20
–10 10
8
– 8
–10 10
8
– 8
– 5 5
4
– 4