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

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12 Practice Tests for the SAT
Practice Test One Answers and Explanations
8. c
Difficulty: Medium
Strategic Advice: Keep in mind that probability is defined
by:
total favorable outcomes = probability
total possible outcomes
Getting to the Answer:
If every 1 Oth person puts his shoes through a machine,
then person 10, person 20, person 30, and so on will put
his shoes through the machine. If every 20th person has his
bag searched, then person 20, person 40, person 60, and
so on will have his bags searched. Since all the people who
have their bags searched also have their shoes checked,
you just need to find the number of people who will have
their bags searched and divide that by the total number of
people. People 20, 40, 60, 80, and 100 will have their bags
searched, so the probability that a passenger will have his or
her bags searched is 160 = 2 1 0 ·
9. D
Difficulty: Medium
Strategic Advice: Pick numbers. To make your work as easy
as possible, make rectangle A a 10-by-10 square.
Getting to the Answer:
The area of A is 1 00. So the width of rectangle B is 7 and
the length of B is 13. The area of rectangle B is 13 x 7 = 91,
which is 9 percent less than that of rectangle A.
10. B
Difficulty: Medium
Strategic Advice: Sometimes the figure as drawn doesn't
contain enough information. Feel free to add to it.
Remember that the interior angles of a triangle add up to
1 80° and that straight angles add up to 1 80°.
Getting to the Answer:
Extend one of the interior line segments to meet line n. This
creates a triangle in which one angle is 1 80° - 120° = 60°,
one angle is 55° because it is an alternate interior angle
along the transverse, and one angle is 1 80° - z0•
60 + 55 + 180 -z = 180
11. D
Difficulty: Medium
115=z
Strategic Advice: On graph problems, all of the information
you need to solve the problem is presented to you! Take
a minute to identify the labels on the x- and y-axes and
find the information you need. Remember that average
.
(arithmetic
.
mean ) =
sum of terms
.
number of terms
Getting to the Answer:
Take the average of the points per game as determined
from the graph:
10 + 14 + 8 + 18 + 20 + 16 = 14.33
6
12. E
Difficulty: Medium
Strategic Advice: Don't feel intimidated by negative or
fractional exponents. Convert negative exponents into
fractions. Express any fractional exponents as the product
of two exponents so that it is easier to reduce the equation.
Backsolving, or plugging the answers into the question
stem, also works well for this type of question.
Getting to the Answer:
.::£
1 X 3 = - 36
1
2 = 36
X3
.2
X3 = 36
55
_l
X3 = 6
_l
(X3)3 = 53
x=216