Educational Talent Search and Upward Bound Forward Service Corporation 14 questions dealing with Pre-Algebra 10 questions from Elementary Algebra 9 questions based on Intermediate Algebra 9 questions from Coordinate Geometry 14 questions from Plane Geometry 4 Trigonometry questions The questions assume knowledge of basic formulas and computational skills but do not require memorization of complex formulas or extensive computation 60 questions 60 minutes Don’t waste time on any one problem, spend your dftime doing as many problems as you can The questions are arranged in order of difficulty RELAX: answering only half of the questions right onwill give you a score of 20 on the Math Section Go Through The Test Twice Take 45 minutes to go through the test Answer the questions that you know how to do Guess on the questions you know you’ll never get Mark the harder questions that you’ll come back to later Spend the last 15 minutes going over the test again Answer the questions you skipped Make sure you have answered every question Spend any remaining time checking your work ALL PROBLEMS ON THE ACT CAN BE SOLVED WITHOUT USING A CALCULATOR You may use a four-function, scientific, or graphing calculator on the Math test Calculators, such as TI-89 and TI-92 are NOT permitted (see page 4 in the ACT prep booklet) Bring a calculator that you know how to use – bringing a more powerful calculator that you do not know how to use isn’t going to help you Read the problem carefully Pay attention to what the question asks you to find Watch for unnecessary information Label the figures with numbers or letters Draw a picture There’s more than one way to solve these problems It’s a timed test – find a quick and reliable way to solve the problem Do your work in your test booklet Be careful using your calculator – it’s easy to push the wrong button Don’t get involved in long, complicated, or tricky calculations Make sure you answered the question that was asked Each of the wrong answers represents a common mistake that you might have made If your answer isn’t one of the choices, reread the question and check your work BACKSOLVE Take advantage of the multiple-choice format and try each answer until you find the one that works. WARNING: Doing it this way will take more time. The greatest common divisor of 84, 90, and 66 (that is, the largest exact divisor of all three numbers) is: A. 6 84 =902٠2٠3٠7 does not go 90 into = 2٠3٠3٠5 84 – eliminate 66 = answer 2٠3٠11 E B. 12 36 does not go into 84 – eliminate answer D C. 18 2٠3 18 = 6does not go into 84 – eliminate answer C D. 36 12 does not go into 90 – eliminate answer B E. 90 6 must be the correct answer and it checks CORRECT ANSWER: A BACKSOLVE (cont) If (3 x ) 1 2 , then x = ? F. 0 G. 2 H. 4 J. 8 K. 10 xxx= 4820 Let Let = Let x== (3 xxx)))x)11 1 12 222 (3(3(3 (3 111 4) 2)0) 22 122 (3(3(3 8) 2.101 2.414 (3 (32) 11 2 2 2.414 0) 2.414 5 31 1 2 2 2.236 2.414 BACKSOLVE (cont) If (3 x ) 1 2 , then x = ? F. 0 G. 2 (3 x ) 1 2 3 x (1 2) 2 H. 4 3 x (1 2)(1 2) J. 8 3 x 1 2 2 2 K. 10 3 x 3 2 2 3 x 3 4 2 3 8 Correct Answer:J GUESSTIMATE If you can estimate the correct answer, then you should be able to eliminate at least one or two answer choices. What is 2% of 60? A. 120 B. 12 C. 1.2 D. 0.12 E. 0.012 120 is greater than 60 – eliminate answer A 60 –xeliminate 0.02 =answer 1.2 B 12 is too large CORRECT ANSWER: C 0.012 is too small – eliminate answer E GUESSTIMATE (cont.) In the right triangle below, how many meters long is AB ? A F. G. H. J. K. 12 7 5 3 ? 4 meters 7 B 3 meters 12, 7, and 5 are longer than the hypotenuse – eliminate answers F, G, and H C GUESSTIMATE (cont.) In the right triangle below, how many meters long is AB ? a b c 2 F. G. H. J. K. 12 7 5 3 7 2 32 b 2 42 9 b 16 2 A 2 ? 4 meters b 7 2 b 7 B CORRECT ANSWER: K 3 meters C EYEBALL By looking at the figure: thetoo ACT, diagrams are “not necessarily” drawn XOne looks bigthe to be 5°- eliminate answer A to scale, but usually they’re quite accurate, so you could X looks too small to be either 60° or 55° - eliminate eliminate certain answer choices by sizing things up with answers E and D your eyes In the figure below, what is the value of x? A. 5° x B. 30° C. 40° D. 55° E. 60° 125° 85° EYEBALL (cont.) In the figure below, what is the value of x? x A. 5° B. 30° C. 40° D. 55° E. 60° 125° 55° 95° 85° 180 –125 = 55 180 - 85 = 95 180 – 55 – 95 = 30 CORRECT ANSWER: B EYEBALL (cont.) By looking at the figure: Lola is making the circle graph below showing the A looks of larger than 99°– eliminate answer F high number students at each grade level in her school. should the–measure A? K A looksWhat smaller than be 240° eliminateofanswer F. 99° G. 120° H. 133° J. 167° K. 240° 240 freshmen 200 sophomores A 130 seniors 150 juniors EYEBALL (cont.) Total number of students = 720 Total number of freshmen = 240 Total number of degrees in a circle = 360° number of freshmen degrees in A number of students degrees in circle 240 A 720 360 CORRECT ANSWER: 240(360) 720 A 86400 720 A 120 A G PICK NUMBERS Some problems are hard because they’re general or abstract, so replace variables with specific numbers If kx + k = 0, and k>1, then x = ? A. 0 Pick a value for k that is greater than 1 B. -1 Let k = 2 Let k = 5 C. 1 kx + k = 0 kx + x = 0 D. -k 2x + 2 = 0 5x + 5 = 0 E. k 2x = -2 5x = -5 x = -1 x = -1 PICK NUMBERS (cont.) If kx + k = 0, and k>1, then x = ? A. 0 kx + k = 0 B. -1 k(x+1) = 0 C. 1 k= 0 OR x+1 = 0 D. -k k= 0 OR x = -1 E. k CORRECT ANSWER:B PICK NUMBERS (cont.) For all a 0, what is the slope of the line segment connecting (a,b) and (-a,b) in the usual (x,y) coordinate plane? F. 0 a G. b b H. a b J. a K . 2a ( x1 , y1 ) and (x2 , y2 ) y1 y2 m x1 x2 Let a = 1 and b = 2 (1,2) and (-1,2) 22 0 0 1 (1) 2 Let a = -1 and b = -2 (-1,-2) and (1,-2) 2 (2) 0 0 1 1 2 PICK NUMBERS (cont.) For all a 0, what is the slope of the line segment connecting (a,b) and (-a,b) in the usual (x,y) coordinate plane? F. 0 a G. b b H. a b J. a K . 2a ( x1 , y1 ) and (x2 , y2 ) y1 y2 m x1 x2 (a, b) and ( a, b) bb 0 m a ( a ) 2a CORRECT ANSWER: F Question 1 In the figure below, CA is perpendicular to AB and CB is perpendicular to BD; AB is 3 units long, AC is 4 units long, and BD is 12 units long. How many units long is CD ? D C A. 13 B. 17 4 A 12 3 C. 19 D. 24 B E. 25 a b c 2 2 5 12 CD 2 2 3 4 CB 2 2 9 16 CB 25 CB 2 2 169 CD 2 2 13 CD 5 CB 13 CORRECT ANSWER: A D 5 4 A 2 25 144 CD 2 C 2 12 3 B ABC is a 3-4-5 right triangle and BCD is a 5-12-13 right triangle Question 2 In the figure below, line m is parallel to line n, and line t is a transversal crossing both m and n. Which of the following lists has 3 angles that are all equal in measure? a b c d e t m n A. a,b,d B. a,c,d C. a,c,e D. b,c,d E. b,c,e CORRECT ANSWER: A Question 3 A shirt that originally cost $35 is on sale at 20% off. If the sales tax on shirts is 5% of the purchase price, how much would it cost to buy the shirt at its sale price? CORRECT ANSWER: D 35 (.20) = 7 A. $ 7.35 35 – 7 = 28 28 (.05) = 1.40 B. $20.00 28 + 1.40 = 29.40 C. $26.60 D. $29.40 35 (.80) = 28 E. $29.75 28 (1.05) = 29.40 Question 4 What is the slope of the line x = 2y +3? CORRECT ANSWER: A A. B. C. D. 1 2 1 3 2 2 E. 3 x = 2y + 3 x – 3 = 2y x 3 y 2 x 3 y 2 2 1 3 x y 2 2 y = mx + b 1 m 2 3 b 2 Question 5 In the figure below, A, C, and D are collinear. If the measure of A is 30 and the measure ofBCD is 120, what is the measure of B? A. 30 B B. 60 C. 90 A D. 120 C D E. 150 In the figure below, A, C, and D are collinear. If the measure of A is 30 and the measure of BCD is 120, what is the measure of B? CORRECT ANSWER: C B 90 A 30 180 – 30 – 60 = 90 60 120 C D 180 – 120 = 60 Question 6 If the area of a circle is , what is the length of its circumference? A. 1 B. 2 C. D. 2 E. 3 Areacircle = r2 Circumference = 2r = r2 C = 2(1) 1 = r2 C = 2 1=r CORRECT ANSWER: D Question 7 What is the value of x in the solution for the system of equations below? 2x + 5y = 20 6x – ½ y = 29 A. 4 B. 5 C. 6 D. 15 E. 20 What is the value of x in the solution for the system of equations below? 2x + 5y = 20 6x – ½ y = 29 2x + 5y = 20 6x – ½ y = 29 multiply by 10 add equations together solve for x 2x + 5y = 20 60x - 5y = 290 62x = 310 x=5 What is the value of x in the solution for the system of equations below? CORRECT ANSWER: B 2x + 5y = 20 6x – ½ y = 29 solve for y substitute into 1st equation solve for x 12x – y = 58 -y = 58 – 12x y = -58 + 12x 2x + 5(-58+12x) = 20 2x + -290 + 60x = 20 62x + -290 = 20 62x = 310 x=5 Question 8 1 2 3 4 5 ? 2 3 4 5 6 A. B. C. D. E. 1 6 17 27 13 18 7 9 5 6 1 2 3 20 2 3 4 30 1 2 4 4 2 3 3 6 1 8 2 2 9 3 1 8 6 2 9 9 1 2 2 9 9 4 13 18 18 18 CORRECT ANSWER: C Question 9 For all y, 26y – (-10y) – 3y(-y+3) = ? A. 10y 26y – (-10y) – 3y(-y+3) B. -3y2 + 25y 26y +10y +3y2 – 9y C. 3y2 + 7y 3y2 +27y D. 3y2 + 25y E. 3y2 + 27y CORRECT ANSWER: E Question 10 In ABC shown below, BD bisects ABC. The measure of ABC is 100, and A measures 30. What is the measure of BDC? C A. 65 D B. 70 C. 75 D. 80 E. 85 30 A 100 B In ABC shown below, BD bisects ABC. The measure of ABC is 100, and A measures 30. What is the measure of BDC? C A. 65 B. 70 C. 75 30 D 80° 100 50 50 A B D. 80 180 – 30 – 50 = 100 E. 85 180 – 100= 80 m BDC = 80 CORRECT ANSWER: D Question 11 In the figure below, S is a right angle, RS is 3 units long, and ST is 4 units long. If the measure of R is x, then sin x = ? T 3 A. 5 3 B. 4 4 C. 4 5 5 D. 4 x 5 E. R 3 S 3 In the figure below, S is a right angle, RS is 3 units long, and ST is 4 units long. If the measure of R is x, then sin x = ? T opposite sin x hypotenuse a2 + b2 = c2 32 + 42 = 5 c2 4 9 + 16 = c2 25 = c2 5=c 4 sin x 5 x R 3 RST is a 3-4-5 right triangle S CORRECT ANSWER: C Question 12 In the figure below, the lengths of DE, EF, and FG are given, in units. What is the area, in square units, of triangle DEG? A.29 B.47.5 G C.60 D.6 149 E.120 10 D 12 E 7 F In the figure below, the lengths of DE, EF, and FG are given, in units. What is the area, in square units, of triangle DEG? G 10 D 12 E 7 AreaTriangle = ½ base x height = ½ (12) (10) = 60 CORRECT ANSWER: C F Question 13 In the figure below, A and B lie on the circle centered at O, OA is 6 units long, and the measure of AOB is 60°. How many units long is minor arc AB? A 6 A. B. 2 C. 6 D. 12 E. 36 O 60 B Circumference = 2r degrees = arc C = 26 arc circle C = 12 60 x 360 12 60(12) = 360 x A 6 O 720 = 360 x 2 = x 60 B CORRECT ANSWER: B Question 14 In the right triangle below, the length of AB is 13 units and the length of CB is 12 units. What is the tangent of A? A. B. C. D. E. 12 5 13 12 12 13 5 12 5 13 A 13 C 12 B opposite tan x adjacent a2 + b2 = c2 122 + b2 = 132 144 + b2 = 169 b2 = 25 12 tan x 5 b=5 CORRECT ANSWER: A A 13 5 C 12 B Question 15 Points N and J have coordinates (-1, -1) and (3,3) respectively. What is the length of line NJ ? (the distance between ( x1 , y1 )and ( x2 , y2 ) ) Distance Formula = A. 4 B. 8 C. 6 ( x2 x1 )2 ( y2 y1 )2 (3 (1))2 (3 (1))2 42 42 32 16 2 4 2 D. 8 E. 4 2 CORRECT ANSWER: E Question 16 What is the cost in dollars to carpet a room x yards long and y yards wide if the carpet costs two dollars per square foot? x yards = 3x feet y yards = 3y feet A. xy B. 2xy Arearectangle= length x width C. 3xy = 3x(3y) = 9xy square feet Total Cost = area x price D. 6xy = 9xy (2) = 18xy E. 18xy CORRECT ANSWER: E Question 17 In the figure below, the largest possible circle is cut out of a square piece of tin. The area of the remaining piece of tin is approximately (in square inches) 2 inches A. 0.14 B. 0.75 C. 0.86 D. 1.0 E. 3.14 Question 17 In the figure below, the largest possible circle is cut out of a square piece of tin. The area of the remaining piece of tin is approximately (in square inches) 2 inches Areacircle = r2 A. 0.14 B. 0.75 12 = = 3.14 1 C. 0.86 Areasquare = s2 D. 1.0 E. 3.14 22 = 4 Areapiece = Areasquare - Areacircle CORRECT ANSWER: C 4 – 3.14 = 0.86 Question 18 Which of the following is equal to 3.14 x 106? A. 314 3.1400000000 B. 3140 C. 31,400 D. 314,000 E. 3,140,000 3140000.0000 CORRECT ANSWER: E Question 19 Find the last number in the series: 8, 4, 12, 6, 18, 9,? A. 19 B. 20 C. 22 D. 24 E. 27 84 8-4=4 or 82=4 412 4+8=12 or 4x3=12 126 12-6=6 or 122 = 6 6 18 6+12=18 or 6x3=18 189 18-9=9 or 182 = 9 9x3=27 CORRECT ANSWER: E Question 20 Lyndsey receives grades of 91, 88, 86, and 78 on four tests. What grade must she receive on her fifth test to have an average test score of 85? A. 82 Let B. 83 (91 + 88 + 86 + 78 + x ) 5 = 85 C. 84 343 + x = 425 D. 85 x = 82 E. 86 x = the fifth test score CORRECT ANSWER: A Question 21 One angle, A, has 3 times the measure of its supplement, B. What is the degree measure of A? A. 112 ½° B. 120° Let x = the measure of B then 3x = the measure of A C. 135° x + 3x = 180° D. 150° 4x = 180° B = 45° E. 157 ½° x = 45° A = 135° CORRECT ANSWER: C Question 22 A bag contains 4 red jelly beans, 5 green jelly beans, and 3 white jelly beans. If a jelly bean is selected at random from the bag, what is the probability that the jelly bean selected is green? A. B. C. D. E. 1 12 1 5 5 23 5 12 5 7 Probability of drawing a green jelly bean number of green jelly beans 5 total number of jelly beans 12 CORRECT ANSWER: D Question 23 For all positive values of a, b, and c with a<b and a>c, which of the following MUST be true? I. a+b>c II. 2a>c III. a+c>b c<a<b I. a and b are both greater than c, so their sum will also be – TRUE A. I only II. B. II only III. If c=2, a=4, and b=10, then a+c<b - FALSE C. I and II only D. II and III only E. I, II, and III a>c, so 2a>c – TRUE CORRECT ANSWER: C Question 24 The scales on both axes of the standard (x,y) coordinate plane below are the same. Of the following, which is the best estimate for the slope of AB ? A. 4 3 B. 4 1 C. 4 1 D. 4 E. -4 1 rise slope = run 4 A B 1 C CORRECT ANSWER: C Question 25 In the figure below, D is a point on AB and E is a point on BC such that DE AC. If DB = 4, AB = 10, BC = 20, what is the length of EC ? B A. 4 B. 6 D C. 8 E D. 10 E. 12 A C CORRECT ANSWER: E ABC and DBE are similar triangles, so their sides are in proportion 4 10 20-x 20 4 20 10(20 x ) 80 200 10x 120 10x x 12 B 4 10 D 6 A 20 20-x E x C Things to Remember on the Math ACT Don’t read the directions Bring a calculator that you know how to use Read the question carefully Pay attention to what the question asks you to find Watch for unnecessary information Draw a picture Pace yourself (60 questions/60 minutes) Things to Remember on the Math ACT Do the easy questions first, then try the hard ones Show some work and circle your answers in your test booklet Don’t waste too much time on one problem Eliminate wrong answers before guessing Answer every question Check your work Work for the whole 60 minutes