UPCAT Math Reviewer Solution

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    UPC A T REVI EWE

    ANSWER KEY AND SOLUTION TO

    UPCAT MATHEMATICS REVIEWER(60 ITEMS)

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    ANSWER KEY

    1 D 13 C 25 D 37 D 49 B2 C 14 C 26 C 38 A 50 C

    3 A 15 D 27 BONUS 39 D 51 D

    4 B 16 C 28 B 40 B 52 B

    5 C 17 D 29 B 41 C 53 C

    6 B 18 D 30 A 42 D 54 C

    7 B 19 C 31 A 43 C 55 D

    8 D 20 A 32 A 44 C 56 A

    9 B 21 D 33 D 45 C 57 C

    10 C 22 C 34 A 46 D 58 B

    11 A 23 B 35 A 47 A 59 A

    12 D 24 C 36 C 48 A 60 D

    SOLUTION

    1. Amanda wants to buy a graphing calculator that is already on sale for P4200.The sale price is %30 below the original price. If she is able to get an additional

    %15 off for being a student, how much money was saved from the original price?

    (A) P1,890.00 (B) P1,170.00 (C) P2,000.00 (D) P2,430.00

    Solution:

    To get the original price divide P4200 by 0.7 the result is P6,000.00.

    Amanda paid P4200 x 0.85 which is equal to P3,570.00

    Amanda saved P6,000 P3,570.00 = P2,430.00.

    Answer: D

    100%-30%

    100%-15%

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    2. Let r and s be the roots of the quadratic equation .0211332 x x x x x x

    Evaluate: 331

    221

    111

    sr sr sr .

    (A) 41 (B) 17

    3 (C) 118 (D) 15

    4

    Solution :If we simplify the quadratic equation, the result is

    .023265 222 x x x x x x .0183 2 x x

    .3

    1and3

    8 rssr

    Simplify 33

    122

    111

    1sr sr sr

    931

    421

    11

    sr rssr rssr rs

    938

    331

    1

    438

    231

    1

    138

    31

    1

    938

    331

    1

    438

    231

    1

    138

    31

    1

    4

    1113

    41

    118

    Answer : C

    Recall:

    If r and s are the roots of

    02 cbxax then

    sum of roots =ab

    sr

    product of roots =ac

    rs

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    3. Solve for x: 53 563025 x(A) 3 (B) 4 (C) 6 (D) 8

    Solution:

    53 563025 x 532 56655 x x divide both sides by

    25

    33 5665 x x3

    3030x

    3x

    Answer: A

    4. The x-intercepts of a parabola are 2 and 4, and the y-intercept is 8. If theparabola passes through the point (a,8), what is the value of a?

    A) 5 (B) 6 (C) 7 (D) 8

    8,a

    0,4 0,2

    8,0

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    Solution: 42 x xk y , when x = 0, 4020k y 88k 1k

    The equation of the parabola is 42 x x y 842 aa

    8862

    aa062 aa

    06aa6or0 aa ,

    a = 6

    Answer: B

    5. Sa isang lungsod, 2/5 ng mga lalaking may sapat na gulang ay kasal sa 5/7 ngbabaeng may sapat na gulang. Ang bilang ng mga kasal na kalalakihan at kasal nakababaihan ay pantay-pantay, at ang mga may sapat na gulang ng populasyon ayhigit sa 3400. Ano ang pinakamaliit na posibleng bilang ng mga may sapat nagulang na residente sa lungsod?

    (A) 3442 (B) 3452 (C) 3432 (D) 3412

    Solution:

    Let x = number of meny = number of women

    y x75

    52

    So y x1425

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    Also x y2514

    x and y are integersso n y 14 for a certain integer nthis implies that n x 25

    3400y x34001425 nn

    340039 n

    18.8739

    3400n

    The smallest possible integer n is 88.

    Therefore 3432883939 n y x

    Answer: C

    6. An acute angle is formed by two lines of slope 1 and 7. What is the slope of the line which bisects this angle?

    (A) 23 (B) 2 (C) 3 (D) 4

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    x y

    x y 7

    Solution:

    The angle of inclination of the line x y 7 is O452

    therefore 7452tan O

    7tan452tan-1

    45tan2tanO

    O

    7tan2-1 12tan

    2tan7712tan

    432tan

    Using half-angle tangent formula

    2

    2tantan

    2sin2cos1 [

    432tan , using Pythagorean triple 3-4-5, 5

    42cos and 532sin ]

    53

    541

    45

    45

    1tan

    If the angle of inclination of the line

    bmx y is then

    tanm

    Recall:

    B A

    B A B A

    tantan1tantan

    tan

    half-angle tangent formulas

    B B

    B B B

    cos1sin

    sincos1

    2tan

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    31

    The angle of inclination of the angle bisector is O45 Therefore the slope of the angle bisector is equal to O45tan

    OO

    45tantan145tantan

    45tan

    tan11tan

    311

    131

    2

    Answer: B

    7. The altitude to the hypotenuse of a triangle with angles of 30 and 60 is 3 units. What is thearea of the triangle in square units?

    (A) 29 (B) 36 (C) 39 (D) 26

    Solution:

    30O

    60 O

    3 units

    units 6

    units 32

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    base = 6 units

    height = units 32

    Area = hb2

    1

    32621

    unitssquare36

    Answer: B

    8. What was the Biblical approximation to ?

    (A) 3.14 (B)7

    22(C) 3.1416 (D) 3

    Answer: D

    9. In the freshman class at Uno High School, there are 18 boys and 12 girls. The average height

    of the boys is 170 cm, and that of the girls is 160 cm. What is the average height of all thestudents in the class?

    (A) 165 cm (B) 166 cm (C) 167 cm (D) 168 cm

    Average height = cm1218

    1601217018

    = cm166

    Answer: B

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    2 16 30

    10. Having found that 2 x is a factor of 3023 23 x x x xP , which of the following isanother factor of xP ?(A) 3 x (B) 6.10 x(C) 1583 2 x x(D) none of the above

    Solution:

    We divide xP by 2 xWe use synthetic division

    1583 2 x x is not factorable

    Answer: C

    11. Gawing simple: 3262 .(A) 2 (B) 3 (C) 4 (D) 6

    Solution:

    32

    32

    32

    62

    34

    32622

    32348

    6

    3 2 1 30

    3 8 15 0

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    32324

    344

    2

    Answer: A

    12. Nicole and Chris have the same grade average before the final exam. The final examcounted as 20% of the semester grade. Nicole got 7 percentage points higher than Chris on hersemester grade, and the final exam was worth 100 points. What is the number of points in thepositive difference between their final exam grades?

    (A) 30 (B) 25 (C) 50 (D) 35

    Solution:Let x be the number of points that Nicole got on her final examand y be the number of points that Chris got on his final exam.

    Then

    72.0 y x multiply both sides by 5

    35y x

    Answer: D

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    13. Suppose there is a row of lockers numbered 1 through 50 with all the doors closed. Astudent is going to walk up and down the lockers opening and closing the locker doors. If a dooris closed the student will open it, and if it is open, it will be closed .If the student starts withmultiple of one, and continues through multiples of 50. How many lockers are open when thestudent is finished?

    (A) 5 (B) 10 (C) 7 (D) 8

    Solution:

    If a number is a perfect square it has an odd number of factors if not it has an even number of factors.

    Example is 9 the factors of 9 are 1,3,9 there are 3 factors and 3 is an odd number12 is not a perfect square. The factors of 12 are 1,2,3,4,6,12, there are 6 factors and 6 is an even number

    Locker # 9 : multiple of 1 (open), multiple of 3 (close), multiple of 9 (open)

    All lockers with a perfect square number are open when the student is finished the remaining lockers areclosed.

    Locker # 12: multiple of 1(open), multiple of 2 (close), multiple of 3 (open), multiple of 4 (close),multiple of 6 (open), multiple of 12 (close)

    The number of perfect squares less than 50 is 7 because 22 8507 .

    7 lockers are open.

    Answer: C

    14. Ang isang mag-aalahas ay may 3 spheres ng ginto. Ang sukat ng kanilang radius ay 3mm, 4mm,at5mm .Kung ang lahat ng tatlong spheres ay tinunaw at bumuo ng panibagong sphere na ginto. Ano angsukat ng radius ng bagong sphere na ginto?

    (A) 8mm (B) 9mm (C) 6 mm (D) 10 mm

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    15. Congruent circles of centers A and B intersect such that AB is a radius of each circle. If AB=4 cm, what is the number of square centimeters in the area ACBD that is common to the twocircles?

    (A) 343

    16 (C) 38

    316

    (B) 343

    32

    (D) 383

    32

    Solution:

    If 4 AB then 4 BC because radii of the same circle are equal

    224

    BX

    ABCD Why? Because CD and AB are diagonals of rhombus ACBD . Diagonals of arhombus are perpendicular and bisect each other

    O90CXBmO30 BCX because BC is twice BX

    So O60CBX

    Therefore O120CBD by symmetry

    A B

    C

    D

    Recall:

    In a 30 O-60 O-90 O triangle.

    The hypotenuse is twice the sideopposite of the 30 O angle.

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    Area of shaded part = area of the sector with central angle CBD minus area of CBD

    Area of sector:

    Area of CBD:

    Area of sector with central angle CBD

    =

    O2

    360

    r

    =

    O

    O2

    360120

    4

    =3

    16

    If 2 BX then 32CX

    Therefore 34CD

    Area of CBD = 2heightbase

    2

    BX CD

    2

    234

    34

    Recall:

    In a 30 O-60 O-90 O triangle.

    The side opposite of the 60 O

    angle is 3 times the length of the side opposite of the 30 O

    angle.

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    Area of shaded part:

    Area ACBD that is common to the two circles:

    Answer: D

    Area of shaded part = area of the sector with central angle CBD minus area of CB

    343

    16

    area ACBD that is common to the two circles

    =

    343

    162

    = 383

    32 because of symmetry

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    16. The value of 11

    3232 is(A) 5 (C) 1/5(B) -5 (D) -1/5

    Solution:

    113232

    11132

    1)1(32

    132

    15

    51

    Answer: C

    17. What is the sum of the first 100 positive odd integers?(A) 25000 (C) 20000(B) 50000 (D) 10000

    Solution:

    nn aan

    S 12[This is the formula for the first n terms of an arithmetic series]

    The 100 th positive odd integer is 2(100) 1 = 199

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    So 19912

    100100S

    20050

    10000

    Answer: D

    18. Sa orasan ni Ginoong Abad ay 5:14 a.m. nang siya ay umalis ng bahay. Bumalik siyamakalipas ang 7 oras at 11 minuto, subalit nagtaka siya dahil 4:33 pa lang ng umaga sa orasan.Naalala niyang nagkaroon pala ng rotating brown out sa kanilang lugar kaya nang bumalik angkuryente ay kusang bumalik sa oras na 12:00 a.m. ang orasan. Anong oras ng umaga bumalik ang kuryente?

    (A) 8:52 (C) 5:52(B) 6:52 (D) 7:52

    Solution:

    The time 7 hours and 11 minutes after 5:14 a.m. is 12:25p.m.

    The time 4 hours and 33 minutes before 12:25 p.m. is 7:52 a.m.

    Answer: D

    19. Express in lowest terms:632

    72

    23

    nnnn

    (A)9n

    n(B)

    97

    nn

    C)9

    2

    nn

    (D)

    7

    2

    nn

    Solution:

    Factor the numerator and denominator and cancel the common factors

    97

    7632

    7 22

    23

    nnnn

    nnnn

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    9

    2

    nn

    Answer: C

    20. How many square units are in the area defined by the set of points (x,y) in the first quadrantwhich satisfies 2010 y x ?

    (A) 150 B) 152 (C) 154 (D) 144

    Solution:

    Answer: A

    20 units

    10 units

    20 units

    10 units

    Area of shaded region = Area of big triangle

    minus Area of small triangle

    = unitssquare150502002

    10102

    2020

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    21. Fibonacci gave a famous problem about reproducing rabbits. After n months, there is apopulation of nr rabbits, where 10r , 21r , 32r and so on. What was the rabbit population

    at n=12 months?

    (A) 55 (B) 89 (C) 144 (D) 233

    Solution:

    The 12 th term of the sequence 1,2,3,5,8,13,21,34,55,89,144,233 is 233

    Answer: D

    22. For what value of x does ? 17154321 x

    (A) 17 (B) 16 (C) 18 (D) 21

    Solution:

    171

    21 x x

    18x , we disregard the negative root

    Answer: C

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    24. What is the measure of the obtuse angle formed by two intersecting angle bisectors of anequilateral triangle?

    (A) 150 (B) 110 (C) 120 (D) 100

    Solution:

    Answer: C

    25. We select 6 numbers at random, with replacement, from the set of integers from 1 to 300inclusive. What is the probability that the product of the 6 numbers is even?

    (A) 3231 (B) 1 (C) 64

    61 (D) 6463

    Solution:Let A= event that the product of 6 numbers selected at random , with replacement, from the setof integers from 1 to 300 inclusive is even.

    So A C = event that the product of 6 numbers selected at random, with replacement, from the setof integers from 1 to 300 inclusive is odd.

    The product of 6 numbers is odd if each number is an odd number.6

    300150

    )(

    C AP

    6

    2

    1

    641

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    Therefore

    )(1)( C AP AP

    641

    1

    6463

    Answer: D26. A deep well 5 feet in diameter is of unknown depth (to the water level). If a 5-foot post iserected at the edge of the well, the line of sight from the top of the post to the edge of the watersurface below will pass through a point 0.4 feet from the lip of the well below the post. Whatis the depth of the well (to the surface of the water)?

    (A) 37.5 ft (B) 47.5 ft (C) 57.5 ft (D) 67.5 ft

    Solution:

    5.57 xAnswer: C

    The figure is not drawn into scale.

    ft AB 5

    ft BP 5

    ft BC 4.0

    Let ft x BD

    ADE ABC ~

    Ratio of corresponding sides of similar trianglesare equal

    DE AD

    BC AB

    55

    4.05 x

    2524.0 x

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    27. Find integers p and q such that32

    334is a root (zero) of the quadratic polynomial

    q px x2 .

    (A) p = -2 and q =11 (C) p = -12 and q = 5

    (B) p = -6 and q = 8 (D) p = -4 and q=9

    Solution:

    First we simplify32

    334

    34)3(336348

    32

    32

    32

    334

    1321

    The other root of the quadratic polynomial is the conjugate of 3 21 which is 321 .

    Sum of roots = 2)321()321(

    Product of roots = 11121)32()1()321)(321( 22

    Therefore the quadratic equation is

    0roots)of (productroots)of (sum2 x x

    01122 x x

    2 p and 11q

    Bonus: No answer in the given choices

    321

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    28. Barb has two watches, one of which loses 6 seconds every 24 hours and the other gains 1second per hour. He sets both of them to the correct time at 8:00 p.m. How many hours will passbefore the positive difference in the time shown is 4 hours?

    (A) 11484 (B) 11520 (C) 11511 (D) 11518

    Solution:

    After 1 hour the difference is seconds45

    246

    1

    hours11520hourshour1

    minutes60minute1seconds60

    secondshours

    516

    hoursseconds4

    5hours4

    Answer: B

    29. Kung ang 203 x , ano ang halaga ng x9 ?(A) 30 (B) 400 (C) 180 (D) 729

    Solution:203 x , we get the square of both sides

    22 203 x

    4009 x

    Answer: B

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    30. Kayang tapusin ng unang pintor ang trabaho sa loob ng 7 oras. Samantalang ang ikalawangpintor ay kayang tapusin ang parehong trabaho sa loob ng 13 oras. Ilang minuto matatapos angtrabaho kung magtutulungan ang dalawang pintor?

    (A) 273 (B) 276 (C) 270 (D) 275

    Solution:

    1131

    71

    x x multiply both sides by LCD = 91

    91713 x x

    9120 x

    hours2091

    x

    minutes273

    Answer: A

    31. Summa Cum Laundry Inc. now has 5000 customers. Its number of customers increases by20 % each year. At the end of how many full years will its number of customers first exceed

    10,000?

    (A) 4 (B) 3 (C) 5 (D) 6Solution:

    Number of customers atthe end of 1st year 60002.150002nd year 72002.160003rd year 86402.17200

    4th year 10000103682.18640

    Answer: A

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    32. Which of the following is equal to 63 454 .

    (A) 3 128 (B) 3 56 (C) 9 216 (D) 6 112

    Solution:

    First term:33 22754

    33 227

    3 23

    Second term:6 26 24

    62

    2

    31

    2

    3 2

    Therefore333333363 12826426424223454

    Answer: A

    33. On a number line, how many integers are no more than 8 units from 20 and also at least 10units from 35?

    (A) 18 (B) 12 (C) 15 (D) 14

    Solution:

    A= Set of integers no more than 8 units from 20 = 28,27,26,25,24,23,22,21,20,19,18,17,16,15,14,13,12

    B = Set of integers at least 10 units from 35 = ,...50,49,48,47,46,4525,24,23,22,21,20,19,18,17,16,15,14,13,12,11,10,9...,

    25,24,23,22,21,20,19,18,17,16,15,14,13,12 B A

    The number of elements in B A is 14.

    Answer: D

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    34. Ang limang magkakasunod na integer ay may average na x . Ano ang pinakamababanginteger?

    (A) x-2 (B) x-3 (C) x-4 (D) x-5

    Solution:

    Since there are 5 consecutive integers and the average is x then there are 2 integers above x and2 integers below x . The integers are 2,1,,1,2 x x x x x . The smallest integer is 2 x .

    Answer: A

    35. The lines 55 xk y and 72x y are perpendicular if k=

    (A) 11/2 (B) 5 (C) -2/9 (D) 9/2

    Solution:

    The product of the slopes should be equal to -1 because they are perpendicular.

    152 k 1102k

    112k

    211k

    Answer: A

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    1

    36. Find the length of the radius of the circle .0364 22 y y x x(A) 2 (B) 3 (C) 4 (D) 9

    Solution:

    0364 22 y y x x

    364 22 y y x x 9439644 22 y y x x

    1632 22 y x

    4r

    Answer: C

    37. Given that1

    0222 z y x

    z y x, find the value of 444 z y x .

    (A) 52 (B) 3

    1 (C) 3 (D) 21

    Solution:

    First equation:

    0z y x get the square of both sides

    0222222 yz xz xy z y x

    1222 yz xz xy divide both sides by 2

    21

    yz xz xy get the square of both sides

    41222 222222222 xyz z xy yz x z y z x y x

    Recall:

    the equation of the circle is

    222 r k yh x

    center: k h,

    length of radius: r

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    0022 z y x xyz

    41

    So41222222 z y z x y x

    Second equation:

    1222 z y x get the square of both sides

    1222 222222444 z y z x y x z y x

    12 222222444 z y z x y x z y x

    Therefore21444 z y x

    Answer: D

    38.Simplify: 22

    11

    cb

    cb

    (A) cbbc1

    (C) bc1

    (B)cb

    bc (D) bc

    cb

    Solution:

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    Multiply the numerator and denominator by bc the result is,

    222211

    cbbcbc

    bcbc

    cbcb

    , factor the denominator and cancel the common factor

    cbcbbccb

    cbbc1

    Answer: B

    39. Let 6if 116if 11

    x x

    x x x f . Find 612 f f

    (A) -4 (B) 28 (C) 40 (D) 18

    Solution: 23111212 f 51166 f

    18523612 f f

    Answer: D

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    We solve 0211 2x

    0211 x

    121 x

    121 x

    02 x

    0 x

    So if x=0, then the expression on the left side of the inequality is undefined

    Therefore 0 x **

    Multiply both sides of the inequality

    92211

    42

    2

    x x

    xby 2211 x , the result is

    22 211924 x x x We dont change the direction of the inequality because we multiplyboth sides by a positive number

    x x x x 21222924 2

    x x x x x 21184182244 22

    182221184 x x x

    Let x y 21

    So x y 212

    Also 162184 2y x

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    And 7111822 2y x

    The inequality 182221184 x x x in terms of y is

    711162 22 y y y

    0716112 23 y y y , we can use synthetic division to find the factors of the left side

    0721 2 y y divide both sides by 21 y a positive number so dont change the direction

    of the inequality [ So 1 y ]

    072 y

    2

    7 y express this inequality in terms of the variable x

    27

    21 x square both sides [the resulting inequality is true because both sides are positive]

    449

    21 x

    445

    2 x

    845 x ***

    21

    x *

    0 x **

    845

    x ***

    The intersection of the above inequalities is

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    0845

    21

    xexcept x

    Answer: C

    42. All the sides of a given triangle are whole numbers. The perimeter of the triangle is 110inches and one side has measure 29 inches. What is the fewest number of inches that can be thelength of one of the remaining sides?

    (A) 30 (C) 26

    (B) 24 (D) 27

    Solution:

    Let a and b be the length of the other two sides where ba

    The perimeter is 110 so 11029ba or 81ba

    29ba

    2981 bb

    522b

    26b

    The smallest possible length of one of the remaining sides is inches27 .Answer: D

    43. If a regular polygon has 27 diagonals, how many sides does it have?

    (A) 12 (C) 9

    (B) 6 (D) 7

    Solution:

    2723nn

    543nn

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    05432 nn

    069 nn

    6or9 nndisregard 6n

    Answer: C44. If a and b are each chosen from the set 10,5,3,2,1 , what is the largest possible value of

    ab

    ba

    ?

    (A) 20 (C)101

    10

    (B)2112 (D)

    212

    Solution:b=1 b=2 b=3 b=5 b=10

    a=1 2 1/2 3 1/3 5 1/5 10 1/10a=2 2 1/2 2 1/6 2 9/10 5 1/5a=3 3 1/3 2 1/6 2 4/15 3 19/30a=5 5 1/5 2 9/10 2 4/15 2 1/2a=10 10 1/10 5 1/5 3 19/30 2 1/2

    the largest possible value of ab

    ba

    is101

    10 .

    Answer: C

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    45. Which of the following relations are functions?

    I. 422 y x IV. 12y x

    II. x y x 2 V. 12x y

    III. x y 4 VI.22 y x

    (A) I, II, III(B) II, III, IV(C) II, III, V(D) I, IV, VI

    Solution: I. 422 y x IV. 12y x

    II. x y x 2 is a linear function

    III. x y 4 is a function V. 12x y is a quadratic function

    VI.22 y x

    Answer: C

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    There are 6 diameters that can be formed using 12 points that are spaced evenly around a circle.Therefore the number of triangles having all their vertices at three of these 12 points, that are of the type 906030 is 2446 .

    Answer: A

    48. Find all the values of x satisfying the given conditions:3

    31

    x y ,

    43

    2x

    y , and

    321 y y(A) 39 (B) 49 (C) 59 (D) 69

    Solution:

    321 y y

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    34

    33

    3 x xmultiply both sides by 12

    363334 x x

    3693124 x x

    363 x

    39 x

    Answer: A

    49. The lines x y 2 and x y2 are

    (A) parallel (B) perpendicular (C) horizontal (D) vertical

    Solution:

    The slopes of the lines x y 2 and x y2 are 2 and21

    respectively.

    The slopes are negative reciprocal of each other. Therefore the two lines are perpendicular.

    Answer: B

    50. Suppose the following two quadratic equations052 k x x and 0392 k x x

    have a non-zero root in common. What is the value of k?(A) 4 (B) 5 (C) 6 (D) 7Solution:

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    Let p and q be the roots of 052 k x x

    q and r be the roots of 0392 k x x

    q is the common root

    5q p 9r qk pq * k qr 3 **

    Using * and **k k

    pqqr 3

    pr 3So the equation 9r q becomes 93 pq

    pq 39 , substitute this in the equation 5q p

    It becomes 539 p p

    42 p

    2 p , therefore 3q

    632pqk Answer: C

    (A) 4 (B) 5 (C) 6 (D) 7

    51. Let x, y, and z represent lengths of the sides of a right triangle with y

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    22

    222 156 z y

    z y x

    2

    22 156 x

    x x

    2

    22 156 x

    x x

    2

    221 x

    x

    21

    Answer: D

    52. The arithmetic mean of 14 numbers is what percent of the sum of the same 14 numbers?.Express your answer as a decimal to the nearest hundredth.

    (A) 7.69% (B) 7.14% (C) 8.33% (D) 5.88%

    Solution:

    Let x be the sum of the 14 numbers

    Arithmetic mean =14 x

    14114

    x

    x

    %14.7Answer: B

    53. Let x x x f ln and x denotes the number of primes less than or equal to x . When

    Gauss was 15 years old, he conjectured that as x goes to infinity, the ratio of x to x f approaches one. Use Gausss estimate to estimate the percentage of positive integers smallerthan 10010 which are prime. (Remark: the natural logarithm of 10 is about 2.3 . )

    (A) 10% (B) 3% (C) 0.4% (D) 0.05%

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    Solution:

    percentage of positive integers smaller than 10010 which are prime

    = 100100

    10primearewhich10ansmaller thintegerspositiveof number

    100

    100

    1010 f because as x goes to infinity x f x

    100

    100

    100

    1010ln

    10

    10010ln1

    10ln1001

    3.21001

    2301

    %4.0Answer: C

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    54. Given that 381m and 64nm . Find the value of mn.(A) -1/2 (C) -3/4(B) -1 (D) -1/4

    Solution:

    381m

    14 33 m

    14m

    41

    m

    43

    mn

    Answer: C

    55. What is the sum of all the elements of this finite arithmetic sequence3, 6, 9, 12, 15, 18, ... , 42 ?

    (A) 314 (B) 313 (C) 318 (D) 315

    Solution:

    14...654321342...181512963

    We can use the formula for the sum of the first n natural numbers. 2

    1...321

    nnn

    64nm

    6441

    n

    344 n

    3n

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    21514

    314...6543213

    315

    Answer: D

    56. The mean, median and mode for this set of data are all equal:{ x, 68,30,58,52} . Find x .

    (A) 52 (B) 68 (C) 58 (D) 30

    Solution:

    x x

    552583068

    x x 5208

    2084 x

    52 x

    mean = median = mode = 52

    Answer: A

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    58. Ang produkto ng dalawang buong numero ay 100,000. Kung ang alinman sa mga numer o ayhindi multiple ng 10, ano ang kanilang suma(sum) ?

    (A) 3158 (B) 3157 (C) 3159 (D) 3160

    Solution:510100000

    552

    55 52

    312532

    3157312532

    Answer: B

    59. Solve for x: x

    22

    3019

    3011

    3019

    (A) 11/30 (C) 2/5(B) 1/3 (D) 3/10

    Solution:22

    301930113019

    x

    3019

    3011

    3019

    3011

    3019

    x

    1

    308

    3019

    30

    11

    Answer: A

    Recall:

    bababa 22

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    60. A triangle with vertices A(0,0), B(8,0), and C(8,6) is graphed in a coordinate plane. The

    triangular region determined by these points is rotated 360 about the x-axis forming ageometric solid. How many square units are in the total outside area of this geometric solid?

    (A) 90 (C) 120

    (B) 84 (D) 96

    Solution:

    Base area is:

    2r A

    The surface area of a cone is therefore given by:

    rsr SA 2

    sr r SA where r=radius of the base

    h = height

    s = length of the side

    s can be calculated by using the Pythagorean theorem

    22 hr s

    r=6, h=8, 1086 22s

    961066SA Answer: D