12.Practice.Tests.for.the.SAT_2015-2016_1128p

12 Practice Tests for the SAT
Practice Test Six Answers and Explanations 585
I
Getting to the Answer:
3y - 33x = 12, put in x = 0 to get
6. D
3y = 12
y=4
Difficulty: Medium
Strategic Advice: Even though there are only variables in
the question, Picking Numbers would still be a great strategy
to try here.
Getting to the Answer:
Pick 6 for an even integer:
(d - l)(d + l) = (6 - 1)(6 + 1) = (5)(7) = 35; too large
Pick 4:
(d - l)(d+ 1)=(4-1)(4 + 1)= (3)(5) = 15
7. A
Difficulty: Medium
Strategic Advice: Whenever you see underlined text in a
question, it usually indicates very important information.
Each number can only satisfy exactly one of each of the
conditions. This type of problem is easiest if you look at
the answer choices and use process of elimination. First
eliminate the answer choices that have none or more than
one even number. Then eliminate the answer choices that
have none or more than one multiple of 3.
Getting to the Answer:
Eliminate (B), (C), and (E) since they all have more than
one even number.
Eliminate (D) because it has has two multiples of 3.
Choice (A) has one even number (10), one odd multiple of
3 (15), and one number that satisfies neither of the other
two requirements, so (A) is the correct choice.
8. D
Difficulty: Medium
Strategic Advice: Even though this question uses the word
percent, you are never asked to find the actual percent
itself. Set this problem up as a ratio to get the answer
more quickly.
Getting to the Answer:
16-6 x- 12
-- --
6 12
9. B
10 x- 12
- --
6 12
120 = 6(x - 12)
120=6x-72
192 = 6x
32 =x
Difficulty: Low
Strategic Advice: Questions involving graphs are usually
relatively straightforward. The graph itself contains all the
information you need. If you just figure out what you are
being asked to find and then pull the necessary information
out of the graph, you'll be well on your way to solving this
question.
Getting to the Answer:
Let's look at the four continents. Africa went from 200,000
cases in 1960 to 50,000 cases in 1970, which is ± of
the number in 1960. Asia went from 1 50,000 cases in
1 960 to 40,000 cases in 1 970, a little more than ± of the
1960 number. Europe went from 50,000 cases in 1960
to around 5,000 cases in 1 970, l of the 1 960 number.
And finally, North America went from 60,000 cases in 1 960
to 20,000 in 1 970, t of the 1 960 number. Therefore,
only Europe had in 1970 less than t of the cases it had in
1960, making the answer (B).
10. E
Difficulty: Medium
Strategic Advice: Before you dive into a question, you
should always make sure you know exactly what you are
trying to solve for. Remember the formula:
(actual change)
percent change =
x 1000/o
(original amount)