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

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1 2 Practice Tests for the SAT
Practice Test Three Answers and Explanations
Getting to the Answer:
Pick numbers:
a=-1
b=2
(A) a + b = -1 + 2 = 1
(B) -ab = -(-1 )(2) = 2
(C) ab = (- 1 )(2) = -2
b 2
(D) - = - = -2
a -1
(E) b - a = 2 - (- 1) = 3
Choice (B) is correct.
8. D
Difficulty: Medium
Positive but not even
Positive and even
Even but not positive
Even but not positive
Positive but not even
Strategic Advice: Set up two proportions of gallons of paint
over square feet and cross-multiply.
Getting to the Answer:
2 gallons _
q ga llons
875 ft2 - 4,375 ft2
2(4,375) = 875g
9. A
8,750 = 875g
lO=g
Difficulty: Medium
Strategic Advice: First, determine the total volume of the
bigger box (volume = length x width x height). Then divide
that by 60 to determine the volume of each smaller box. Go
through the answer choices to see which dimensions can
work.
Getting to the Answer:
Volume bigger box = (24)(10)(15) = 3,600
Volume of each smaller box = 3,5 oo = 60
60
Check the answer choices:
Volume = length x width x height
(A) (2)(5)(6) = 60
(A) works. Stop here.
The other answers are wrong:
(B) (3)(4)(6) = 72
(C) (3)(5)(6) = 90
(D) ( 4)(5)(6) = 120
(E) (5)(6)(12) = 360
10. E
Difficulty: Medium
Incorrect
Incorrect
Incorrect
Incorrect
Strategic Advice: The average is the sum of the terms
divided by the number of terms. The question stem gives
you a range for the sum of the terms, so all you need to
do is divide the smallest and the greatest by the number of
terms ( 4) to determine the range of the average.
Getting to the Answer:
53 = nl
4 4
57 =14
l
4 4
The average is between 13 ..!_ and 14 l . Only (E) works.
4 4
11. c
Difficulty: Medium
Strategic Advice: Use the Pythagorean theorem to
determine the hypotenuse, which the triangles share, and
use the theorem again to determine side AD.
Getting to the Answer:
First triangle (you may have recognized this as a multiple of
a 3:4:5 triplet) :
a2 +b2 = c2
(8)2 + (6)2 = c2
64 + 36 =c2
100 =c2
lO=C
Second triangle:
a2 + b2 =c2
(5)2 + b2 = (10)2
25 + b2 = 100
b2 =75
b=v7s
= v25>