Sat 2015 Practice Test #1 Answer Explanations

Choice B is correct.
The amounts given in the table are in 
thousands of dollars. Therefore, the amount in the annual budget for 
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change in the annual budget for agriculture/natural resources from 
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2
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Choices A and C are incorrect and may result from errors in setting 
up or calculating the average rate of change. Choice D is incorrect; 
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QUESTION 23 
Choice B is correct.
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_
4 = 
_
2 
. Similar estimates
6 
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_
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4; for education, a ratio of slightly
_
greater than 2 
; for highways and transportation, a ratio of slightly
less than 56; and for public safety, a ratio of slightly greater than 
5 
9.
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further from the corresponding ratio for human resources than the 
corresponding ratio for education. 
48(67,21
Choice A is correct.
The equation of a circle can be written as 
(
[ơ
h
)
2
+ (
y
ơ
k
)
2
= 
U
2
where (
h
, 
k
) are the coordinates of the center 
of the circle and 
U
is the radius of the circle. Since the coordinates 
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[
2
+ (
y
ơ
2
= 
U
2
. The radius of the circle is the distance from the center, 
_
4
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endpoint of a radius, 
( 
, 5 
)
. By the distance formula,
U
2 
_
4 
2 
_
25
= 
( 
ơ
) 
ơ
2
= 9 . Therefore, an equation of the given circle is
[
2
+ (
y
ơ
2
= 
_
25
9 .

---

_
25
Choices B and D are incorrect. The equations given in these choices 
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results from using 
U
instead of 
U
2
in the equation for the circle. 
QUESTION 25