1- Choice D is correct
The correct answer is − 248 Use PEMDAS (order of operation): [8×(−32)+12] + 4 − [8 × 2] ÷ 2 = [− 256 + 12] + 4 − [16] ÷ 2 = [− 256 + 12] + 4 − [8] = [− 244] + 4 − [8] = [− 244] + 4 − 8 = − 248
|
2- Choice A is correct
The correct answer is 12 x2 − 5 x y − 2 y2 Use FOIL method. (4 x + y) (3 x − 2 y)=12 x2 − 8 x y+3 x y−2 y2=12 x2−5 x y − 2 y2
|
3- Choice C is correct
The correct answer is 24 To solve absolute values equations, write two equations y−7 could be positive 5, or negative 5. Therefore, y−7= 5 ⇒ y = 12 y−7= −5 ⇒ y = 2 Find the product of solutions: 2 × 12 = 24
|
4- Choice B is correct
The correct answer is − 23 The equation of a line in slope intercept form is: y=mx+b Solve for y. 3 x − 2 y = 8 ⇒ − 2 y = 8 − 3 x ⇒ y = (8 − 3 x) ÷ (− 2) ⇒ y = 1.5 x − 4 The slope of this line is 1.5. The product of the slopes of two perpendicular lines is − 1. Therefore, the slope of a line that is perpendicular to this line is: 𝑚1 × 𝑚2=− 1⇒1.5×𝑚2=− 1⇒𝑚2=− 23
|
5- Choice D is correct
The correct answer is − 27 Plug in the value of x and y. x=1 and y=5 2 (x − 3 y) + (4 − y)(4 − y) = 2 (1 − 3 (5)) + (4 − 5) (4 − 5) = 2 (1 − 15) + (− 1) (− 1) = 2 (− 14) + 1 = − 27
|
6- Choice B is correct
The correct answer is 20 Let x be the number. Write the equation and solve for x. 60% of x = 12 ⇒ 0.6 x = 12 ⇒ x = 12 ÷ 0.6 = 20
|
7- Choice B is correct
The correct answer is 10 x is 1.5 times of y, then x=1.5 y ⇒ (x=15) 15 = 1.5 × y ⇒ y = 15 ÷ 1.5 = 10
|
8- Choice C is correct
The correct answer is 2 hours The distance between Alex and Jack is 12 miles. Jack running at 4 miles per hour and Alex is running at the speed of 10 miles per hour. Therefore, every hour the distance is 6 miles less. 12 ÷ 6 = 2
|
9- Choice D is correct
The correct answer is 80% The failing rate is 6 out of 30 = 630 Change the fraction to percent: 630 × 100% = 20% 20 percent of students failed. Therefore, 80 percent of students passed the exam.
|
10- Choice D is correct
The correct answer is 16 24= 2×2×2×2= 16
|
11- Choice A is correct
The correct answer is 2 ≤ x < 3 Solve for x. 2 ≤ 3x−4 < 5 ⇒ (add 4 all sides) 2+4 ≤ 3x < 5+4 ⇒ 6 ≤ 3x < 9 ⇒ (divide all sides by 3) 2 ≤ x < 3 x is between 2 and 3 .
|
12- Choice D is correct
The correct answer is 14 Let x be the width of the rectangle. Use Pythagorean Theorem: a2+b2=c2 42+x2=52 ⇒ x2+16=25 ⇒ x2 = 25−16 = 9 ⇒ x = 3 Perimeter of the rectangle = 2 (length + width) = 2 (4+3) = 2 (7) = 14
|
13- Choice A is correct
The correct answer is 160 The perimeter of the trapezoid is 50 cm. Therefore, the missing side (height) is = 50 \ – \ 14 \ – \ 12 \ – \ 8 = 16 Area of a trapezoid: A = \frac{1}{2}\ h \ (b_1 \ +\ b_ 2) = \frac{1}{2} \ (16) \ (12 \ + \ 8) = 160
|
14- Choice C is correct
The correct answer is \frac{1}{3} The probability of choosing a diamond is \frac{21}{63} = \frac{1}{3}
|
15- Choice D is correct
The correct answer is : \frac{1}{3}<0.35<36\%<65\% Change the numbers to decimal and then compare. \frac{1}{3} = 0.333... 0.35 36% = 0.36 65% = 0.65 0.333...<0.35<0.36<0.65
|
16- Choice C is correct
The correct answer is 84.5 average (mean) = \frac{sum \ of \ terms}{number \ of \ terms}⇒ 85 = \frac{sum \ of \ terms}{40}⇒ sum = 85 × 40 = 3400 The difference of 92 and 72 is 20. Therefore, 20 should be subtracted from the sum. 3400 - 20 = 3380 mean = \frac{sum \ of \ terms}{number \ of \ terms}⇒ mean = \frac{3380}{40} = 84.5
|
17- Choice C is correct
The correct answer is \frac{1}{6} To get a sum of 6 or 8 for two dice, we should get 3 and 3, or 2 and 4, or 1 and 5 or 3 and 5 or 2 and 6 or 4 and 4. Therefore, there are 6 options. Since, we have 6 × 6 = 36 total options, the probability of getting a sum of 6 and 8 is 6 out of 36 or \frac{1}{6}.
|
18- Choice D is correct
The correct answer is 10 Use formula of rectangle prism volume V = (length) (width) (height) ⇒ 1500 = (20) (7.5) (height) ⇒ height =1500 \ ÷ \ 150 = 10
|
19- Choice C is correct
The correct answer is 8 To find the number of possible outfit combinations, multiply the number of options for each factor: 4 × 1 × 2 = 8
|
20- Choice B is correct
The correct answer is : 12 4 \ ÷ \ \frac{1}{3} = 12
|
21- Choice A is correct
The correct answer is : 50 The diagonal of the square is 10. Let x be the side. Use Pythagorean Theorem: a^2 + b^2 = c^2 x^2 + x^2 = 10^2 ⇒ 2\ x^2 = 10^2 ⇒ x^2 = 50 ⇒ x = \sqrt{50} The area of the square is: \sqrt{50} × \sqrt{50} = 50
|
22- Choice D is correct
The correct answer is : \frac{1}{5} Probability = \frac{number \ of \ desired\ outcomes}{number \ of\ total \ outcomes} = \frac{12}{20 + 12 + 12 + 16} = \frac{1}{5}
|
23- Choice D is correct
The correct answer is 37 Find the difference of each pairs of numbers: 2, 4, 7, 11, 16, 22, 29, ___, 46 The difference of 2 and 4 is 2, 4 and 7 is 3, 7 and 11 is 4, 11 and 16 is 5, 16 and 22 is 6, 22 and 29 is 7, 29 and next number should be 8. The number is 29 + 8 = 37
|
24- Choice B is correct
The correct answer is 13.33 The width of the rectangle is twice its length. Let x be the length. Then, width =2\ x Perimeter of the rectangle is 2 (width + length) = 2 \ (2\ x \ + \ x ) = 80 ⇒ 6\ x = 80 ⇒ x = 13.33 The length of the rectangle is 13.33 meters.
|
25- Choice B is correct
The correct answer is : 32 average = \frac{sum \ of \ terms}{number \ of \ terms} ⇒ (average of 6 numbers) 16 = \frac{sum \ of \ terms}{6} ⇒ sum of 6 numbers is 16 × 6 = 96 (average of 4 numbers) 8 = \frac{sum \ of \ numbers}{4} ⇒ sum of 4 numbers is 4 × 8 = 32 sum of 6 numbers - sum of 4 numbers = sum of 2 numbers ⇒ 96 - 32 = 64 (average of 2 numbers) = \frac{64}{2} = 32
|
26- Choice D is correct
The correct answer is 0 Solving Systems of Equations by Elimination Multiply the first equation by (-3), then add it to the first equation. -\ 3 \ (3\ x \ +\ y = 9) x \ +\ 3\ y = 3 ⇒ -\ 9\ x \ -\ 3\ y = -\ 27 ⇒ -\ 8\ x = -\ 24 ⇒ x = 3 x \ +\ 3\ y = 3 Plug in the value of x into one of the equations and solve for y. 3\ (3) + y = 9 ⇒ y = 0
|
27- Choice A is correct
The correct answer is 35 Solve for the sum of four numbers. average = \frac{sum \ of \ terms}{number \ of \ terms} ⇒ 32 = \frac{sum \ of \ 4 numbers}{4} ⇒ sum of 4 numbers = 32 \ ×\ 4 = 128 The sum of 4 numbers is 128. If a fifth number 47 is added, then the sum of 5 numbers is 128 \ +\ 47 = 175 average = \frac{sum \ of \ terms}{number \ of \ terms} = \frac{175}{5} = 35
|
28- Choice D is correct
The correct answer is 5 Th ratio of boy to girls is 3: 7. Therefore, there are 3 boys out of 10 students. To find the answer, first divide the total number of students by 10, then multiply the result by 4. 30 ÷ 10 = 3 ⇒ 3 × 3 = 9 There are 9 boys and 21 (30 - 9) girls. So, 5 more boys should be enrolled to make the ratio 2:3
|
29- Choice C is correct
The correct answer is \frac{1}{6} 5000 out of 30000 equals to = \frac{5000}{30000} = \frac{5}{30} = \frac{1}{6}
|
30- Choice A is correct
The correct answer is 150\ x + 38000 ≤ 50000 Let x be the number of new shoes the team can purchase. Therefore, the team can purchase 150\ x. The team had $50000 and spent $38000. Now the team can spend on new shoes $12000 at most. Now, write the inequality: 150\ x \ + \ 38000 ≤ 50000
|
31- Choice D is correct
The correct answer is 65 Jack needs an 70\% average to pass for four exams. Therefore, the sum of 4 exams must be at lease 4 \ × \ 70 = 280The sum of 3 exams is: 63 + 67 + 85 = 215 The minimum score Jack can earn on his fifth and final test to pass is: 280 \ -\ 215 = 65
|
32- Choice B is correct
The correct answer is \frac{1}{3} \frac{1}{4}\ x \ - \ \frac{1}{6} = \frac{-\ 1}{12} ⇒ \frac{1}{4}\ x = \frac{-\ 1}{12} \ + \ \frac{1}{6} = \frac{1}{12} ⇒ \frac{1}{4}\ x = \frac{1}{12} Multiply both sides by the reciprocal of the coefficient of x (\frac{4}{1}) \frac{1}{4}\ x = \frac{1}{12} (\frac{4}{1}) ⇒ x = \frac{1}{3}
|
33- Choice D is correct
The correct answer is 2160 Use simple interest formula: I=prt (I = interest, p = principal, r = rate, t = time) I = (18000) (0.03) (4) = 2160
|
34- Choice D is correct
The correct answer is 21\ x^5\ y^4 Simplify. 3\ x\ y^2 \ (7\ x^4 \ y^2 ) = 21\ x^5 \ y^4
|
35- Choice A is correct
The correct answer is 110\ π\ i n^2 Surface Area of a cylinder = 2\ π\ r\ (r\ +\ h), The radius of the cylinder is 5\ (10 \ ÷\ 2) inches and its height is 6 inches. Therefore, Surface Area of a cylinder = 2\ π\ (5 )\ (5 \ +\ 6 ) = 110 \ π
|
36- Choice B is correct
The correct answer is \frac{512}{1331} The square of a number is \frac{64}{121}, then the number is the square root of \frac{64}{121} \sqrt{\frac{64}{121}} = \frac{8}{11} The cube of the number is: (\frac{8}{11})³ = \frac{512}{1331}
|
37- Choice B is correct
The correct answer is 12 Write the numbers in order: 2,4,12,14,21 edian is the number in the middle. So, the median is 12.
|
38- Choice D is correct
The correct answer is 100 miles Use the information provided in the question to draw the shape. Use Pythagorean Theorem: a^2 + b^2 = c^2 60^2 \ + \ 80^2 = c^2 ⇒ 3600 \ + \ 6400 = c^2 ⇒ 10000 = c^2 ⇒ c = 100 miles
|
39- Choice C is correct
The correct answer is 25.55 Plug in 78 for F and then solve for C. C = \frac{5}{9} (F \ -\ 32) ⇒ C =\frac{5}{9}(78 \ -\ 32) ⇒ C = \frac{5}{9}(46) = 25.55
|
40- Choice D is correct
The correct answer is 34 First, find the number. Let x be the number. Write the equation and solve for x. 250 % of a number is 100, then: 2.5 × x = 100 ⇒ x =100 ÷ 2.5 = 40 85 % of 40 is 34
|
41- Choice D is correct
The correct answer is 1 Solve for y . 3\ x \ -\ 3\ y = 1 ⇒ -\ 3\ y = 1 \ -\ 3\ x ⇒ y = x \ - \ \frac{1}{3} The slope of the line is 1.
|
42- Choice D is correct
The correct answer is 126 Volume of a box = length × width × height = 3 × 6 × 7 = 126
|
43- Choice D is correct
The correct answer is ( 5\ x^4\ +\ 3\ x^3 ) (3\ x \ + \ 4\ x^3 \ +\ 3\ x^4) \ +\ (-\ x^3 \ -\ 3\ x\ + \ 2\ x^4) ⇒ ( 3 \ x^4\ + \ 4\ x^3\ +\ 3\ x ) \ +\ ( 2\ x^4\ -\ x^3\ -\ 3\ x) = ( 5\ x^4 \ + \ 3\ x^3 )
|
44- Choice A is correct
The correct answer is 145\% the population is increased by 10\% and 12\% and 18\% . 10\% increase changes the population to 110\% of original population. For the second increase, multiply the result by 112\%. For the third increase, multiply the result by 118\% (1.10) \ × \ (1.12) \ × \ ( 1.18) = 1.45 = 145\%
|
45- Choice C is correct
The correct answer is 72000 Three times of 30000 is 90000. One fifth of them cancelled their tickets. One fifth of 90000 equals 18000. 72000 (90000 – 18000 = 72000) fans are attending this week
|
46- Choice D is correct
The correct answer is 88.4 The area of the square is 488.41. Therefore, the side of the square is a square root of the area. \sqrt{488.41} = 22.1 Four times the side of the square is the perimeter: 4 \ ×\ 22.1 = 88.4
|