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

12 Practice Tests for the SAT
Practice Test Three Answers and Explanations I
299
4. E
Difficulty: Low
Strategic Advice: With multiple unknowns, solving for one
will often help you solve the unknown that the question is
asking about.
Getting to the Answer:
j=3(4) +4= 16
k = 3(16) + 4 = 52
5. A
Difficulty: Medium
Strategic Advice: She will clean the house on days 7,
14, 21 ... (multiples of 7) and do laundry on days 5, 10,
15 ... (multiples of 5). Think about what has to be true of
days where both happen.
Getting to the Answer:
The least common multiple of 7 and 5 is 35. So every 35th
day, she will do both. This will happen 3 31 = 9 times.
6. E
Difficulty: Medium
Strategic Advice: Any side of a triangle must be larger than
the difference between the other two sides and less than
the sum of the other two sides.
Getting to the Answer:
In (E), 12 = 5 + 7, so the "triangle" would be totally flat.
7. E
Difficulty: Medium
Strategic Advice: Remember, slope is rise or Y 2 - Yi , so a
run x 2
-x 1
slope of zero means the line is horizontal (rise = O), and an
undefined slope means the line is vertical (run = O).
Getting to the Answer:
This line is vertical, so the x-coordinate stays the same. The
only answer choice with the same x-coordinate is (E).
8. B
Difficulty: Medium
Strategic Advice: Remember that you can always
assume the diagram is drawn to scale, unless you're told
otherwise. Use this to eliminate wrong answer choices if
you get stuck.
Getting to the Answer:
Draw a third line parallel to I and m. Find the supplements
of the given angles. The angle we want has been split into
two angles, each of which is an alternate interior angle with
one of the supplements, so q = 30° + 20° = 50°.
9. 760
Difficulty: Low
160'
Strategic Advice: Be sure to read percent problems
carefully. Pay particular attention to what a percent is ofis
it some percent of the total number of passengers, or of
the married passengers, or of some other group?
Getting to the Answer:
800/o of 3,000 = 0.8 x 3,000 = 2,400 married passengers
600/o of 2,400 = 0.6 x 2,400 = 1,440 married less than a
year
2,400 - 1 ,440 - 200 = 760 married 1-1 0 years
10. 468
Difficulty: Low
Strategic Advice: Be careful when translating the word
problem into numbers. Be sure to answer the question that
is asked.
Getting to the Answer:
You're told that 35 percent of the 720-person class are boys.
There are 0.35 x 720 = 252 boys. This means that the number
of girls is 720 - 252 = 468. Alternatively, you could use the fact
that if the class was 35 percent boys, then it was 1 000/o - 350/o
= 650/o girls. Therefore, there are 0.65 x 720 = 468 girls.
11. 31
Difficulty: Low
Strategic Advice: You don't even have to turn this into
algebra if you don't want to-just work backward.
m