eliminate (A). Choice (B) becomes 15,000(0.003)^2 = 0.135. Eliminate (B). Choice (C)
becomes 15,000(0.997)^2 ≈ 14,910. The correct answer is (C).
9. B First, calculate what Mike’s daily calorie consumption is during finals. 12% of 1,680 is
0.12 × 1,680 = 201.6. During finals Mike consumes 1,680 + 201.6 = 1,881.6 calories per
day. Whenever the question includes variables, Plug in. Let d = 2. Over 2 days Mike
consumes 2 × 1,881.6 = 3,763.2 calories. He also adds 900 calories at the end of finals.
His total consumption over the entire finals period is 3,763.2 + 900 = 4,663.2 calories, so
4,663.2 is the target number. Plug in 2 for d in each of the answer choices. In (A),
1.12[1,680(2) + 900] = 4,771.2, which is not the target number. Eliminate (A). In (B),
1.12[1,680(2)] + 900 = 4,663.2, which is the target. Leave (B), but check the other answer
choices just in case. In (C), 1.12(1,680 + 900)(2) = 5,779.2, and in (D), [1,680 + (0.12)(2)]
+ 900 = 2,580.24. Eliminate both (C) and (D). The correct answer is (B).
- D Use Process of Elimination on this question. Choice (A) cannot be correct because more
juniors prefer Austin to Pensacola. Choice (B) sounds appealing, but “more than three times
as likely” means the seniors as a whole need to prefer Pensacola more than three times as
much as the juniors do as a whole. Seniors prefer Pensacola 23 out of 42, or 55%. Juniors
prefer it 7 out of 21, or 33%. So, seniors do not prefer Pensacola more than three times as
much as juniors do. You can also eliminate (C) because more than half of all juniors prefer
Austin, while less than half of all seniors prefer Austin. The statement in (D) is correct
because 7 is one-third of the total of 21 juniors.
11. B We are looking for the probability that a randomly selected person is a man with a doctoral
degree. There are 16,232 men with doctoral degrees, and 220,532 total adults aged 25
years or older. So the probability that a randomly selected person fits the category we are
looking for is = 0.07 = 7%, which is (B).
- C Whenever there are variables in the question and in the answers, think Plugging In. If x =
10, then C = 110 + = 110 + 5 = 115 and R = 15(10) – = 150 – = 150 – 10 =
- Therefore, the profit can be calculated as 140 – 115 = 25. Plug 10 in for x in the
answers to see which answer equals the target number of 25. Choice (A) becomes – –
(10) + 110 = – – 31(5) + 110 = –10 – 155 + 110 = –55. This doesn’t match the target
number, so eliminate (A). Choice (B) becomes – – (10) + 110 = – – 29(5) +
110 = –10 – 145 + 110 = –45. Eliminate (B). Choice (C) becomes – + (10) – 110 =
