with the weight of the slices. According to the problem, the slices on each platter weigh
160 ounces. Therefore, the total weight of the slices on all 4 platters is 160 × 4 = 640.
Eliminate (C) because the total is wrong in the weight equation. The correct answer is (D).- D Whenever there are two equations with the same two variables, they can be solved
simultaneously by adding or subtracting them. The key is to get one variable to disappear.
Multiply the second equation by –2, to get 6a – 2z = 20. Stack the two equations and add
them.
Therefore, the correct answer is (D). Be careful of (C)—the question did NOT ask for the
value of a.
B We know that Isabella starts with $1,000 in her account, so this eliminates (D). She is
earning money from the interest, so the line must have a positive slope, eliminating (C),
which has a constant slope. The two best choices are (A) and (B), but in (A) Isabella’s
money doesn’t begin to increase until the 5-year mark, which doesn’t make sense—thus (B)
is the correct answer.
A Find a point on the graph and plug that point into each of the answers to see which equation
works. The graph goes through the point (0, –6). Using that point, (A) becomes –6 = 0^2 – 0
– 6. Solve the right side of the equation to get –6 = –6. Keep (A), but check the remaining
answer choices just in case. Choice (B) becomes –6 = 0 + 0 –12. Solve the right side of the
equation to get –6 = –12. This is not true, so eliminate (B). Choice (C) becomes –6 = 0^2 +
6(0) + 9. Solve the right side of the equation to get –6 = 9. Eliminate (C). Choice (D)
becomes –6 = 0^2 + 5(0) + 6. Solve the right side of the equation to get –6 = 6. Eliminate
(D). The correct answer is (A).
A The key to this problem is understanding that the three friends plan to climb an equal
number of stairs. Start with the building for which we know the number of stairs. The
friends are each planning to climb 3,639 ÷ 3 = 1,213 stairs. Since 1,213 must be a part of
the correct answer, eliminate (B) and (D). Given that Dalia will complete only 75% of her
goal, Dalia’s total must be multiplied by 75% or 0.75. This eliminates (C). The correct
answer is (A).
C Let’s break this question into smaller pieces. First, to find the number of U.S. residents who
visit European countries every year, we will need to determine how many residents hold
passports: 36% of 315 million = 0.36 × 315 = 113.4 million. Next, we can calculate how
many of those passport-holders travel internationally each year: 8% of 113.4 million = 0.08
× 113.4 = 9.072 million. Finally, we can calculate how many of those international
travelers visit Europe each year: 10% of 9.072 million = 0.1 × 9.072 = 0.9072 million.