D Whenever there are variables in the question and in the answers, think Plugging In. Let d =
For $1 the air pump dispenses 90 × 4 = 360 pounds of air. Therefore, for $2 the air pump
will dispense 360 × 2 = 720 pounds of air. Plug in 2 for d in the answer choices to see
which answer equals 720. Choice (A) becomes P = 2 + 90 = 92. Eliminate (A). Choice (B)
becomes P = 2 + 360 = 362. Eliminate (B). Choice (C) becomes P = 90(2) = 180.
Eliminate (C). Choice (D) becomes P = 360(2) = 720. Therefore, the correct answer is
(D).
A Set up a proportion: . Cross-multiply to get x = 6 × 0.30 = 1.8
meters. Therefore, the correct answer is (A).
- B In order to find the undeveloped area, take the entire area of the park and subtract the area
of the developed portions. Subtract the 4 acre lake to get 44 – 4 = 40 undeveloped acres.
Next, subtract the largest and smallest possible soccer field area: 40 – 10 = 30, and 40 – 8
= 32. Therefore, the correct answer is (B).
B Weight is shown on the horizontal axis of the graph, given in tons. Look for the mark
indicating 3 on this axis; then draw a vertical line from that mark to the line of best fit. Once
you hit it, draw a horizontal line over to the vertical axis. It should hit between 20 and 25
miles per gallon, slightly closer to the mark for 25. This makes (B) the correct answer.
Draw your lines carefully, using your answer sheet as a straightedge if necessary, to avoid
trap answers like the close-but-not-quite (C).
C You can see from the graph that from 2000 to 2002, the number of coati increased from 140
to 160. From 2002 to 2004, the number increased from 160 to 180. Therefore, the number
of coati is increasing at a rate of 20 every 2 years. In 2006, if the rate of increase remains
the same, the number of coati should be 180 + 20 = 200, which is (C).
B The question states that there are infinitely many solutions to the equation. That means any
real number should work for d. Plug in an easy number like 0 for every d in the equation to
get . Simplify the equation to = , so a = 10, which is (B).
A First, convert the minutes shown in the graph to seconds. Multiply 15 minutes by 60
seconds to get 900 seconds. Then, since speed is distance divided by time, simply divide
3,000 meters by 900 seconds. The answer is 3.3 m/s, which is (A).
C Plug 2 in for y in the answers to see which function most closely equals the area of 14,910.
Choice (A) becomes 15,000 = 7,500. This does not match the target number, so