7. A Start by labeling the equation with the information in the question. The question says that P
is the price of the item and t is the time in years, so label these. The question also states that
the price increases by $3 per year, so the 3 in the equation is the price increase. Now look
at the answer choices, which are about the number 10 in the equation, and see what can be
eliminated. Choice (D) refers to the price increase, which is 3, so eliminate (D). The other
answer choices refer to the year. Plug in the price given in the question, $43, to solve for t.
The equation becomes 43 = 3t + 10, so 3t = 33, and t = 11. That represents the number of
years from when the item was manufactured until the year 2010, the year of the given price.
Subtract 11 years from 2010 to get 1999, which is (A).
8. C Use the formula arc = rθ, where r is the radius and θ is the measure of the central angle in
radians. Because the angle is already in radians, you just need to plug in 10 for the radius
and the angle into the formula. You then get s = (10) or 4π, which is (C).
9. B Start by calculating the least amount of acetaminophen the child needs. If the child is 75
pounds, then the amount of acetaminophen needed can be calculated as ×1,000 = ×
1,000 = 500. Since only (B) gives 500 as the low-end value, the correct answer is (B).
- C Whenever there are variables in the question and in the answer choices, think Plugging In,
picking numbers that ensure that I is an integer. If P = 18 and R = 2, then I =
=3. Because V = IR, V = 3 × 2 = 6. Plug P = 18, R = 2, and V = 6 into
the answers to see which answer works. Choice (A) becomes 18 = . Solve the right side
of the equation to get 18= . This statement is not true, so eliminate (A). Choice (B)
becomes 18= . This statement is not true, so eliminate (B). Choice (C) becomes 18 = .
Solve the left side of the equation to get 18 = . This statement is true, so keep (C), but
check the remaining answer just in case. Choice (D) becomes 18 = (6^2 )(2^3 ) or 18 = 36 × 8.
This statement is not true, so eliminate (D). The correct answer is (C).
11. D A root of the equation is the same as an x-intercept. In the graph, the function crosses the x-
axis at 4 points. Therefore, the correct answer is (D).
- A Label the congruent angles, ABC and CDE, as such. In order to find the measure of those
angles, use the formula 180(n − 2), where n is the number of sides, to determine the sum of
the interior angles of the figure. Because the figure has five sides, plug 5 in for n to get
180(5 − 2), or 180(3), which equals 540. Subtract 120 to get 420. Subtract 100 to get 320.
