Sat 2015 Practice Test #1 Answer Explanations

Choice B is correct.
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in 
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when 
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or when 
_ 
G
= 
, not when 
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does 
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3 ơG
indicates that the number of phones left will decrease 
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QUESTION 5 
Choice C is correct.
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exponents, can be combined to determine the answer as shown here: 
(
[
2
y
ơ
y
2
+ 5
[\
2
) 
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2
y
[\
2
ơ
y 
2
)
(
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2
\ơơ
= 
[
2
y
))
 
ơ
y
2
ơơ
y
2
)) + (5
[\
2
ơ[\
2
) 
2
[
2
y
= 
[\
2 
2
[
2
y
= + 2
[\
2 
Choices A, B, and D are incorrect and are the result of common 
calculation errors or of incorrectly combining like and unlike terms. 
QUESTION 6 
Choice A is correct.
In the equation 
h
D
+ 28.6, if 
D
, the age of the 
boy, increases by 1, then 
h
becomes 
h
D D 
(
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LQFUHDVHVE\LQFKHVHDFK\HDU
Alternatively: The height, 
h
, is a linear function of the age, 
D
, of 
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Choices B, C, and D are incorrect and are likely the result of dividing 
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KHLJKWLQLQFKHVRIDQHZERUQER\+RZHYHUGLYLGLQJE\RU
2 has no meaning in the context of this question. 

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QUESTION 7