4.5 bl<'n C.·1-1 Answer ExplanationsPS04971
65.A certain bridge^ is^4 ,^024 feet^ long.^ Approximately
how many minutes does it take to cross this
bridge at a constant speed of 20 miles per hour?
(1 mile= 5,280 feet)
(A)^1
(B)^2
(C) 4
(D) 6
(E)^7Arithmetic
First, convert 4,024 feet to miles since
the speed is given in miles per hour:4,024 f{ X 1 ffil ＝ 4,024.
(^5) ,280只 5,280
ffil.
4,024
Now, divide by 20 mph: mi+ 20 mi
5 280 ， 1 hr
= 4,024觅^1 hr 4,024 hr
X =
5 ,280 20觅(5,280)( (^20) )
.
L ast convert ， 4,024 hr to mmutes:
(5,280)(^20 )
4,024 Yr X 60 min = (^4 ,024)(^60 ) min ""
(5,280)(^20 )^1 园(5,280)(^20 )
4 000 ， X — (^60) mm.Then,. 4,000 x— 60
min=
5,000 20 5,000 20
= 0.8 x 3 min"" 2 min. Thus, at a constant speed
of 20 miles per hour, it takes approximately
2 minutes to cross the bridge.
Th e correct answer 1s B.
PS04009
- If S = {O, 4, 5, 2, 11, 8), how much greater than
the median of the numbers in S is the mean of the
numbers in S?
囚＠＠仰们 05112025
Arithmetic; Algebra
The median of S is found by ordering the values
according to size (0, 2, 4, 5, 8, 11) and taking the
4+5
average of the two middle numbers: ——= 4.5.
2sum of n values
The mean is =
n
0+4+5+2+11+ 8
6= (^5).
The difference between the mean and the
median is 5 - 4.5 = 0.5.
1h e correct answer 1s A.
PS12657
6 7. The^ annual^ interest^ rate^ earned^ by^ an^ investment
increased by 10 percent from last year to this year. If
the annual interest rate earned by the investment this
year was 11 percent, what was the annual interest
rate last year?
(A) 1%
(B) 1. 1 %
(C) 9. 1 %
(D) 10 %
(E) 10. (^8) %
Arithmetic
If L is the annual interest rate last year, then
the annual interest rate this year is 10% greater
than L, or 1.lL. It is given that 1.lL = 11%.
Therefore ， L =—11% 一－= 10%. Note that if the
1.1 （
given information had been that the investment
increased by 10 percentage points, then the
equation would have been L + 10% = 11 %.)
The correct answer is D.
PS07394
- A total of 5 liters of gasoline is to be poured into
two empty containers with capacities of 2 liters and 6
liters, respectively, such that both containers will be
filled to the same percent of their respective
capacities. What amount of gasoline, in liters, must be
poured into the 6-liter container?
1
(A) 4-
2
(B) 4
3
(C) 3-
4
(D) 3
1
(E) 1-
4