SAT Practice Test 7, Section 8: Questions 6 - 10

This is for SAT in Jan 2016 or before.

The following are worked solutions for the questions in the math sections of the SAT Practice Tests found in the The Official SAT Study Guide Second Edition.

It would be best that you go through the SAT practice test questions in the Study Guide first and then look at the worked solutions for the questions that you might need assistance in. Due to copyright issues, we are not able to reproduce the questions, but we hope that the worked solutions will be helpful.

6. Correct answer: (D)

Given:
x = −1
k = 0

To find:
Which of the following has the greatest value

Solution:
Topic(s): Exponents

For x = –1
xⁿ = 1, for n even
xⁿ = –1, for n odd

So the greatest value would be the one with the biggest coefficient and the biggest even exponent

Answer: (D) 8kx⁴

7. Correct answer: (E)

Given:
Josephine’s daily routine, consists of swimming, cycling, and running in that order
She runs faster than she swims
She cycles faster than she runs
She does not rest between the activities

To find:
The graph that shows the distance she covers during the entire time of her exercise routine

Solution:

The speed of each activity would determine the slope on the graph.
The faster the activity, the steeper would be the slope.

Comparing the speeds of the 3 activities we get: swimming < running < cycling

We need to find a graph where:
Slope of 1 st segment < slope of 3 rd segment < slope of 2 nd segment

The only graph that fits that description is (E)

Answer: (E)

8. Correct answer: (A)

Given:
is one of the points of intersection of the graphs
y = x² – 7 and y = –x² + j
j is a constant

To find:
The value of j

Solution:
The point of intersection occurs when the two graphs are equal:

x² – 7 = –x² + j
j = 2x² – 7 (equation 1)

We are told that the two graphs intersect at .

Substituting that into equation 1, we get

Answer: (A) 5

9. Correct answer: (A)

Given:

To find:
Which one is a possible value of x

Solution:
Topic(s): Absolute value

The only answer that fits the two inequalities is (A) 4

Answer: (A) 4

10. Correct answer: (C)

Given:
The polygon
All interior angles of the polygon are congruent

To find:
The value of x

Solution:
The sum of exterior angles of a regular polygon is 360º.

The given figure is a 5-sided polygon

Each exterior angle of the polygon is then

Answer: (C) 72