Sat practice Test #8 Answer Explanations

The correct answer is 3 
_ 
2 .
One method for solving the system of 
equations for y is to add corresponding sides of the two equations. 
Adding the left-hand sides gives (−x + y) + (x + 3y), or 4y. Adding the 
right-hand sides yields −3.5 + 9.5 = 6. It follows that 4y = 6. Finally, 
dividing both sides of 4y = 6 by 4 yields y = 6 
— 
4 or
3 
— 
2 . Any of 3/2, 6/4, 9/6, 
12/8 or the decimal equivalent 1.5 will be scored as correct.
QUESTION 19
The correct answer is 8. The number of employees, y, expected to 
be employed by the company x quarters after the company opened 
can be modeled by the equation y = ax + b, where a represents the 
constant rate of change in the number of employees each quarter 
and b represents the number of employees with which the company 
opened. The company’s growth plan assumes that 2 employees will be 
hired each quarter, so a = 2. The number of employees the company 
opened with was 8, so b = 8.
QUESTION 20
The correct answer is 144. In a circle, the ratio of the length of a given 
arc to the circle’s circumference is equal to the ratio of the measure of 
the arc, in degrees, to 360°. The ratio between the arc length and the 
circle’s circumference is given as 2 
— 
5 . It follows that
2 
— 
5 = 
x 
_ 
360 . Solving 
this proportion for x gives x = 144.

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ANSwER ExPlANATIONS
| SAT Practice Test #8
Section 4: Math Test – Calculator
QUESTION 1
Choice A is correct. If one pound of grapes costs $2, two pounds of 
grapes will cost 2 times $2, three pounds of grapes will cost 3 times $2, 
and so on. Therefore, c pounds of grapes will cost c times $2, which is 
2c dollars.
Choice B is incorrect and may result from incorrectly adding instead 
of multiplying. Choice C is incorrect and may result from assuming 
that c pounds cost $2, and then finding the cost per pound. Choice D 
is incorrect and could result from incorrectly assuming that 2 pounds 
cost $c, and then finding the cost per pound.
QUESTION 2