1- Choice D is correct
The correct answer is –\ 122 Use PEMDAS (order of operation): [6\ ×\ (–\ 24)\ +\ 8]\ –\ (–\ 4)\ +\ [4\ ×\ 5]\ ÷\ 2 = [–\ 144\ +\ 8]\ –\ (–\ 4)\ +\ [20]\ ÷\ 2 = [–\ 144\ +\ 8]\ –\ (–\ 4)\ +\ 10 = [–\ 136]\ –\ (–\ 4) \ +\ 10 = [–\ 136]\ +\ 4\ +\ 10 = \ –\ 122
|
2- Choice D is correct
The correct answer is 4\ x^2\ +\ 2\ x\ y \ - \ 2 \ y^2 Use FOIL method. (2\ x\ +\ 2\ y)\ (2\ x\ -\ y) = 4\ x^2\ -\ 2\ x\ y\ +\ 4\ x\ y\ -\ 2\ y^2=4\ x^2\ +\ 2\ x\ y\ -\ 2\ y^2
|
3- Choice D is correct
The correct answer is 91 To solve absolute values equations, write two equations. x\ -\ 10 could be positive 3, or negative 3. Therefore, x\ -\ 10=3 ⇒ x=13 x\ -\ 10=-\ 3 ⇒ x=7 Find the product of solutions: 7\ ×\ 13 = 91
|
4- Choice B is correct
The correct answer is -\frac{1}{2} The equation of a line in slope intercept form is: y=m\ x\ +\ b Solve for y. 4\ x\ -\ 2\ y=12 ⇒ -\ 2\ y=12\ -\ 4\ x ⇒ y=(12\ -\ 4\ x)\ ÷\ (-\ 2) ⇒ y=2\ x\ -\ 6 The slope of this line is 2. The product of the slopes of two perpendicular lines is -\ 1. Therefore, the slope of a line that is perpendicular to this line is: m_1\ ×\ m_2 = -\ 1 ⇒ 2\ ×\ m_2 = -\ 1 ⇒ m_2 = \ -\frac{1}{2}
|
5- Choice C is correct
The correct answer is 36 Plug in the value ofx and y. x=3 and y=-\ 2 5\ (x\ -\ 2\ y)\ +\ (2\ -\ x)^2= 5\ (3\ -\ 2\ (-\ 2))\ +\ (2\ -\ 3)^2=5\ (3\ +\ 4)\ +\ (-\ 1)^2 =36
|
6- Choice C is correct
The correct answer is 10 Let x be the number. Write the equation and solve for x. 40\% of x=4⇒ 0.40\ x=4 ⇒ x=4\ ÷\ 0.40=10
|
7- Choice A is correct
The correct answer is 3 A is 4 times of B, then: A = 4\ B ⇒ (A = 12)\ 12 = 4\ ×\ B ⇒ B = 12\ ÷\ 4 = 3
|
8- Choice C is correct
The correct answer is 6 hours The distance between Jason and Joe is 9 miles. Jason running at 5.5 miles per hour and Joe is running at the speed of 7 miles per hour. Therefore, every hour the distance is 1.5 miles less. 9\ ÷\ 1.5 = 6
|
9- Choice D is correct
The correct answer is 80\% The failing rate is 11 out of 55 = \frac{11}{55} Change the fraction to percent: \frac{11}{55} ×\ 100\%=20\% 20 percent of students failed. Therefore, 80 percent of students passed the exam.
|
10- Choice D is correct
The correct answer is 729 3^6 = 3\ ×\ 3\ ×\ 3\ ×\ 3\ ×\ 3\ ×\ 3 = 729
|
11- Choice D is correct
Solve for x. -\ 2\ ≤\ 2\ x\ -\ 4\ <\ 8 ⇒ (add 4 all sides) -\ 2\ +\ 4\ ≤\ 2\ x\ -\ 4\ +\ 4\ <\ 8\ +\ 4 ⇒ 2\ ≤\ 2\ x\ <\ 12 ⇒ (divide all sides by 2) 1\ ≤\ x\ <\ 6 x is between 1 and 6
|
12- Choice D is correct
The correct answer is 28 Let x be the width of the rectangle. Use Pythagorean Theorem: a^2\ +\ b^2 = c^2 x^2\ +\ 8^2 = 10^2 ⇒ x^2\ +\ 64 = 100 ⇒ x^2 = 100\ –\ 64 = 36 ⇒ x = 6 Perimeter of the rectangle = 2 (length + width) = 2\ (8\ +\ 6) = 2\ (14) = 28
|
13- Choice B is correct
The correct answer is 70 cm^2 The perimeter of the trapezoid is 36 cm. Therefore, the missing side (height) is = 36\ –\ 8\ –\ 12\ –\ 6 = 10 Area of a trapezoid: A = \frac{1}{2}\ h\ (b_1\ +\ b_2) = \frac{1}{2}\ (10)\ (6\ +\ 8) = 70
|
14- Choice B is correct
The correct answer is \frac{1}{4} The probability of choosing a Hearts is \frac{13}{52} =\frac{1}{4}
|
15- Choice D is correct
The correct answer is \frac{2}{3} ,\ 67\%,\ 0.68,\ \frac{4}{5} \frac{2}{3} = 0.666… 0.68 67\% = 0.67 \frac{4}{5} = 0.80 Therefore \frac{2}{3}\ <\ 67\%\ <\ 0.68\ <\ \frac{4}{5}
|
16- Choice C is correct
The correct answer is 87.5 average (mean) =\frac{sum\ of\ terms}{number\ of\ terms} ⇒ 88 =\frac{sum\ of\ terms}{50} ⇒ sum = 88\ ×\ 50 = 4400 The difference of 94 and 69 is 25. Therefore, 25 should be subtracted from the sum. 4400\ –\ 25 = 4375 mean =\frac{sum\ of\ terms}{number\ of\ terms} ⇒ mean = \frac{4375}{50} = 87.5
|
17- Choice D is correct
The correct answer is \frac{5}{36} To get a sum of 6 for two dice, we should get 3 and 3, or 2 and 4, or 4 and 2, or 1 and 5, or 5 and 1. Therefore, there are 5 options. Since, we have 6\ ×\ 6 = 36 total options, the probability of getting a sum of 6 is 5 out of 36 or \frac{5}{36}.
|
18- Choice D is correct
The correct answer is 8 Use formula of rectangle prism volume. V = (length) (width) (height) ⇒ 2000 = (25)\ (10) (height) ⇒ height = 2000\ ÷\ 250 = 8
|
19- Choice C is correct
The correct answer is 60 To find the number of possible outfit combinations, multiply the number of options for each factor: 3\ ×\ 5\ ×\ 4 = 60
|
20- Choice D is correct
The correct answer is 24 4\ ÷\ \frac{1}{6} = 24
|
21- Choice B is correct
The correct answer is 32 The diagonal of the square is 8. Let x be the side. Use Pythagorean Theorem: a^2\ +\ b^2 = c^2 x^2\ +\ x^2 = 8^2 ⇒ 2\ x^2 = 8^2 ⇒ 2\ x^2 = 64 ⇒x^2 = 32 ⇒\ x= \sqrt{32} The area of the square is: \sqrt{32}\ ×\ \sqrt{32} = 32
|
22- Choice B is correct
The correct answer is \frac{1}{4} Probability =\frac{number \ of\ desired\ outcomes}{number \ of\ total\ outcomes} = \frac{18}{12\ +\ 18\ +\ 18\ +\ 24} = \frac{18}{72} = \frac{1}{4}
|
23- Choice D is correct
The correct answer is 30 Find the difference of each pairs of numbers: 2,\ 3,\ 5,\ 8,\ 12,\ 17,\ 23, ___,\ 38 The difference of 2 and 3 is 1,\ 3 and 5 is 2,\ 5 and 8 is 3,\ 8 and 12 is 4,\ 12 and 17 is 5,\ 17 and 23 is 6,\ 23 and next number should be 7. The number is 23\ +\ 7 = 30
|
24- Choice A is correct
The correct answer is 10 meters 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)=60 ⇒ 6\ x=60 ⇒ x=10 The length of the rectangle is 10 meters.
|
25- Choice D is correct
The correct answer is 16 average =\frac{sum\ of\ terms}{number\ of\ terms} ⇒ (average of 6 numbers) 12 = \frac{sum\ of\ numbers}{6} ⇒sum of 6 numbers is 12\ ×\ 6 = 72 (average of 4 numbers) 10 =\frac{sum\ of\ numbers}{4} ⇒sum of 4 numbers is 10\ ×\ 4 = 40 sum of 6 numbers – sum of 4 numbers = sum of 2 numbers 72\ –\ 40 = 32 average of 2 numbers =\frac{32}{2} = 16
|
26- Choice C is correct
The correct answer is -\ 2 Solving Systems of Equations by Elimination Multiply the first equation by (–2), then add it to the second equation. \cfrac{\begin{align}-\ 2\ (2\ x\ +\ 5\ y= 11) \\ \ 4\ x\ -\ 2\ y=-\ 14 \end{align}}{} ⇒-\ 4\ x\ -\ 10\ y= -\ 22\\4\ x\ -\ 2\ y=-\ 14 ⇒ -\ 12\ y= -\ 36 ⇒ y= 3 Plug in the value of y into one of the equations and solve for x. 2\ x\ +\ 5\ (3)= 11 ⇒ 2\ x\ +\ 15= 11 ⇒ 2\ x= -\ 4 ⇒ x= -\ 2
|
27- Choice C is correct
The correct answer is 27 Solve for the sum of five numbers. average =\frac{sum\ of\ terms}{number\ of\ terms} ⇒ 24 = \frac{sum\ of\ 5\ numbers}{5} ⇒ sum of 5 numbers = 24\ ×\ 5 = 120 The sum of 5 numbers is 120. If a sixth number 42 is added, then the sum of 6 numbers is 120\ +\ 42 = 162 average =\frac{sum\ of\ terms}{number\ of\ terms} =\frac{162}{6} = 27
|
28- Choice C is correct
The correct answer is 12 The ratio of boys to girls is 4:7. Therefore, there are 4 boys out of 11 students. To find the answer, first, divide the total number of students by 11, then multiply the result by 4. 44\ ÷\ 11 = 4 ⇒ 4\ ×\ 4 = 16 There are 16 boys and 28\ (44\ –\ 16) girls. So, 12 more boys should be enrolled to make the ratio 1:1
|
29- Choice A is correct
The correct answer is \frac{1}{22} 2,500 out of 55,000 equals to \frac{2500}{55000} =\frac{25}{550} =\frac{1}{22}
|
30- Choice A is correct
The correct answer is 120\ x\ +\ 14,000\ ≤\ 20,000 Let x be the number of new shoes the team can purchase. Therefore, the team can purchase 120\ x. The team had $20,000 and spent $14000. Now the team can spend on new shoes $6000 at most. Now, write the inequality: 120\ x\ +\ 14,000\ ≤\ 20,000
|
31- Choice D is correct
The correct answer is 60 Jason needs an 75\% average to pass for five exams. Therefore, the sum of 5 exams must be at lease 5\ ×\ 75 = 375 The sum of 4 exams is: 68\ +\ 72\ +\ 85\ +\ 90 = 315. The minimum score Jason can earn on his fifth and final test to pass is: 375\ –\ 315 = 60
|
32- Choice D is correct
The correct answer is \frac{1}{4} Isolate and solve for x. \frac{2}{3}\ x\ +\ \frac{1}{6}= \frac{1}{3} ⇒ \frac{2}{3}\ x= \frac{1}{3}\ -\frac{1}{6} =\frac{1}{6} ⇒ \frac{2}{3}\ x=\frac{1}{6} Multiply both sides by the reciprocal of the coefficient of x. (\frac{3}{2})\ \frac{2}{3}\ x= \frac{1}{6}\ (\frac{3}{2}) ⇒ x= \frac{3}{12}=\frac{1}{4}
|
33- Choice B is correct
The correct answer is $840 Use simple interest formula: I=prt (I = interest, p = principal, r = rate, t = time) I=(12000)\ (0.035)\ (2)=840
|
34- Choice D is correct
The correct answer is 48\ x^8\ y^6 Simplify. 6\ x^2\ y^3\ (2\ x^2\ y)^3= 6\ x^2\ y^3\ (8\ x^6\ y^3 ) = 48\ x^8\ y^6
|
35- Choice C is correct
The correct answer is 66\ π\ i n^2 Surface Area of a cylinder = 2\ π\ r\ (r\ +\ h), The radius of the cylinder is 3\ (6\ ÷\ 2) inches and its height is 8 inches. Therefore, Surface Area of a cylinder = 2\ π\ (3)\ (3\ +\ 8) = 66\ π
|
36- Choice C is correct
The correct answer is \frac{125}{512} The square of a number is \frac{25}{64}, then the number is the square root of \frac{25}{64} \sqrt{\frac{25}{64}}=\frac{5}{8} The cube of the number is: (\frac{5}{8})^3 =\frac{125}{512}
|
37- Choice B is correct
The correct answer is 28 Write the numbers in order: 2,\ 19,\ 27,\ 28,\ 35,\ 44,\ 67 The Median is the number in the middle. So, the median is 28.
|
38- Choice D is correct
The correct answer is 170 Use the information provided in the question to draw the shape. Use Pythagorean Theorem: a^2\ +\ b^2 = c^2 80^2\ +\ 150^2 = c^2 ⇒ 6400\ +\ 22500 = c^2 ⇒ 28900 = c^2 ⇒ c = 170
|
39- Choice B is correct
The correct answer is 40 Plug in 104 for F and then solve for C. C = \frac{5}{9}\ (F\ –\ 32) ⇒ C = \frac{5}{9}\ (104\ –\ 32) ⇒ C = \frac{5}{9}\ (72) = 40
|
40- Choice A is correct
The correct answer is 45 First, find the number. Let x be the number. Write the equation and solve for x. 150\% of a number is 75, then: 1.5\ ×\ x=75 ⇒ x=75\ ÷\ 1.5=50 90\% of 50 is: 0.9\ × \ 50 = 45
|
41- Choice D is correct
The correct answer is 2 Solve for y. 4\ x\ -\ 2\ y=6 ⇒ -\ 2\ y=6\ -\ 4\ x ⇒ y=2\ x\ -\ 3 The slope of the line is 2.
|
42- Choice D is correct
The correct answer is 120 cm^3 Volume of a box = length × width × height = 4\ ×\ 5\ ×\ 6 = 120
|
43- Choice A is correct
The correct answer is 4\ x^4\ +\ 4\ x^3\ -\ 12\ x^2 (6\ x^3\ -\ 8\ x^2\ +\ 2\ x^4 )\ -\ (4\ x^2\ -\ 2\ x^4\ +\ 2\ x^3 ) ⇒ (6\ x^3\ -\ 8\ x^2\ +\ 2\ x^4 )\ -\ 4\ x^2\ +\ 2\ x^4\ -\ 2\ x^3 ⇒ 4\ x^4\ +\ 4\ x^3\ -\ 12\ x^2
|
44- Choice C is correct
The correct answer is 38\% the population is increased by 15\% and 20\%. 15\% increase changes the population to 115\% of original population. For the second increase, multiply the result by 120\%. (1.15)\ ×\ (1.20) = 1.38 = 138\% 38 percent of the population is increased after two years.
|
45- Choice C is correct
The correct answer is 60,000 Three times of 24,000 is 72,000. One-sixth of them canceled their tickets. One-sixth of 72,000 equals 12,000\ (\frac{1}{6}\ ×\ 72000 = 12000). 60,000\ (72000\ –\ 12000 = 60000) fans are attending this week
|
46- Choice D is correct
The correct answer is 97.6 The area of the square is 595.36. Therefore, the side of the square is the square root of the area. \sqrt{595.36}=24.4 Four times the side of the square is the perimeter: 4\ × \ 24.4 = 97.6
|