1.
If 4y+8 = 12y + 24, then y = ?
Correct Answer
D. -2
Explanation
To solve the equation, we need to isolate the variable y. First, we can simplify the equation by subtracting 4y from both sides, which gives us 8 = 8y + 24. Then, we can subtract 24 from both sides to get -16 = 8y. Finally, we divide both sides by 8 to find that y = -2.
2.
If f(2) = 10 and f(4) = 44, which of the following could be f(x)?
Correct Answer
C. 3x^{2}- x
Explanation
The given answer, 3x2 - x, could be f(x) because it satisfies the given conditions. When x = 2, the equation evaluates to 3(2)2 - 2 = 12 - 2 = 10. Similarly, when x = 4, the equation evaluates to 3(4)2 - 4 = 48 - 4 = 44. Therefore, 3x2 - x is a possible function f(x) that satisfies the given values.
3.
Line B contains points (3, 2) and (4, 5). If line V is perpendicular to line B, then which of the following could be the equation of line V?
Correct Answer
A. Y = (-1/5)x + 3
Explanation
The equation of a line can be determined using the slope-intercept form, y = mx + b, where m is the slope and b is the y-intercept. To find the slope of line B, we can use the formula (y2 - y1) / (x2 - x1), where (x1, y1) and (x2, y2) are two points on the line. By substituting the given points (3, 2) and (4, 5) into the formula, we find that the slope of line B is (5 - 2) / (4 - 3) = 3. Since line V is perpendicular to line B, its slope will be the negative reciprocal of 3, which is -1/3. Therefore, the equation y = (-1/5)x + 3 matches the given conditions.
4.
If the remainder when x is divided by 5 equals the remainder when x is divided by 4, then x could be any of the following except?
Correct Answer
C. 24
Explanation
If the remainder when x is divided by 5 equals the remainder when x is divided by 4, it means that x is a multiple of both 5 and 4. Since 24 is divisible by both 5 and 4, it cannot be the value of x. Therefore, x could be any of the other options: 20, 22, or 21.
5.
If one packager can pack 15 boxes every two minutes, and another can pack 15 boxes every three minutes, how many minutes will it take these two packagers, working together, to pack 300 boxes?
Correct Answer
A. 24
Explanation
If one packager can pack 15 boxes every two minutes and another packager can pack 15 boxes every three minutes, it means that the first packager can pack 7.5 boxes per minute and the second packager can pack 5 boxes per minute. When working together, their combined rate is 12.5 boxes per minute. To pack 300 boxes, it would take them 300 divided by 12.5, which equals 24 minutes.
6.
The product of integers x and y is divisible by 36. If x is divisible by 6, which of the following must be true?
i. y is divisible by x
ii. y is divisible by 6
iii. y/6 is divisible by 6
Correct Answer
A. None
Explanation
If x is divisible by 6, it means that x can be written as 6 multiplied by some other integer. Since the product of x and y is divisible by 36, it means that y must also be divisible by 6, because 6 multiplied by any integer will be divisible by 6. However, we cannot conclude anything about whether y is divisible by x or whether y/6 is divisible by 6. Therefore, none of the statements i, ii, or iii must be true.
7.
If x > 0 and [3 - √x] [3 + √x] = 7, what is the value of x?
Correct Answer
C. 2
Explanation
By using the difference of squares formula, we can simplify the equation [3 - √x] [3 + √x] = 7 to (3 - √x)(3 + √x) = 7. Expanding this equation gives us 9 - x = 7. Solving for x, we find that x = 2.
8.
If -1 ≤ a ≤ 2 and -3 ≤ b ≤ 2, what is the greatest possible value of (a + b) (b - a)
Correct Answer
D. 9
Explanation
The greatest possible value of (a + b) (b - a) can be achieved when a and b are at their maximum values within the given constraints. The maximum value of a is 2 and the maximum value of b is 2. Substituting these values into the expression, we get (2 + 2) (2 - 2) = 4 * 0 = 0. Therefore, the correct answer is 0.
9.
If the distance from (2, 6) to (1, b) is a, a = [ | -1 | + 16 ]^1/2, and b < a, what is the value of b?
Correct Answer
C. 2
Explanation
The distance between two points in a coordinate plane can be calculated using the distance formula, which is the square root of the sum of the squares of the differences in the x-coordinates and the y-coordinates. In this case, the distance between (2, 6) and (1, b) is given as a. The x-coordinate difference is 2 - 1 = 1, and the y-coordinate difference is 6 - b. Plugging these values into the distance formula, we get the equation a = sqrt(1^2 + (6 - b)^2). Since a is given as sqrt(|-1| + 16), we can set that equal to the equation above. Solving for b, we find that b = 2.
10.
If 3c + 2b + a = 22, b + a = 8 and a = 6, what is the value of c + b + a?
Correct Answer
C. 12
Explanation
Given that a = 6, we can substitute this value into the equation b + a = 8 to find that b = 2. Substituting the values of a and b into the equation 3c + 2b + a = 22, we get 3c + 2(2) + 6 = 22. Simplifying this equation, we find that 3c + 4 + 6 = 22, or 3c + 10 = 22. Subtracting 10 from both sides, we get 3c = 12, or c = 4. Therefore, c + b + a = 4 + 2 + 6 = 12.