Sat 2015 Practice Test #1 Answer Explanations

The correct answer is 96.
Since each day has a total of 24 hours of 
time slots available for the station to sell, there is a total of 48 hours of 
time slots available to sell on Tuesday and Wednesday. Each time slot 
_
LVDPLQXWHLQWHUYDOZKLFKLVHTXDOWRD
1
2-hour interval. Therefore, 
48 hours 
there are
= 96 time slots of
PLQXWHVIRUWKHVWDWLRQ
_
1 
2 hours/time slot 
to sell on Tuesday and Wednesday. 
QUESTION 35 
The correct answer is 6.
The volume of a cylinder is 
ŒU
2
h
, where 
U
is the radius of the base of the cylinder and 
h
is the height of the 
cylinder. Since the storage silo is a cylinder with volume 72
Œ
cubic 
yards and height 8 yards, it follows that 72
Œ
= 
ŒU
2
(8), where 
U
is the 
radius of the base of the cylinder, in yards. Dividing both sides of the 
equation 72
Œ
= 
ŒU
2
(8) by 8
Œ
gives 
U
2
= 9, and so the radius of the base 
RIWKHF\OLQGHULV\DUGV7KHUHIRUHWKH
diameter of the base of the 
cylinder is 6 yards. 
QUESTION 36 
The correct answer is 3.
The function 
h
(
[
LVXQGHƮQHGZKHQWKH
__
1
denominator of
is equal to zero. The expression 
(
[ơ
2
+ 4(
[ơ
(
[ơ
2
+ 4(
[ơ
4 is a perfect square: (
[ơ
2
+ 4(
[ơ 
((
[ơ
2
, which can be rewritten as (
[ơ
2
. The expression (
[ơ
2 
is equal to zero if and only if 
[ 7KHUHIRUHWKHYDOXHRI[
for which 
h
(
[
LVXQGHƮQHGLV
QUESTION 37