1. Hose A can fill a tank in
5 minutes, and Hose B can fill the same tank in 6 minutes. How many tanks would
Hose B fill in the time Hose A fills 6 tanks?
(A)
3
(B)
4
(C)
5
(D)
5.5
(E)
6
Hose
A takes 5 minutes to fill one tank. To fill 6 tanks, it takes 6 × 5 = 30
minutes. Hose B takes 6
minutes
to fill one tank. Hence, in the 30 minutes, it would fill 30/6 = 5 tanks. The
answer is (C).
2. A car traveled at 80 mph
for the first half (by time) of a trip and at 40 mph for the second half of the
trip. What is the average speed of the car during the entire trip?
(A)
20
(B)
40
(C)
50
(D)
60
(E)
80
Let
t be the entire time of the trip.
We
have that the car traveled at 80 mph for t/2 hours and at 40 mph for the
remaining t/2 hours. Remember that Distance = Speed × Time.
Hence, the net distance traveled during the two periods equals 80 × t/2
+ 40 × t/2. Now, remember that
Average Speed =Net Distance/Time
Taken
=80
× t/2 + 40 × t/2/ t
=80
× ½ + 40 × 1/2
=40
+ 20 = 60
The
answer is (D).
3.A
father distributed his total wealth to his two sons. The elder son received 3/5
of the amount. The younger son received $30,000. How much wealth did the father
have?
(A)
15,000
(B)
45,000
(C)
60,000
(D)
75,000
(E)
89,000
Suppose
x and y are the amounts received in dollars by the elder and the
younger son, respectively.
Then
the amount the father had is x + y.
The
elder son received 3/5 of the amount. Expressing this as an equation yields
x = (3/5)(x + y)
x = (3/5)x + (3/5)y
(2/5)x
= (3/5)y
x = (3/2)y
Hence,
x + y, the amount father had, equals 3y/2 + y = 5y/2
= (5/2)(30,000) [Given that the younger son received 30,000 dollars] = 75,000,
and the answer is (D).
4.
John has $42. He purchased fifty mangoes and thirty oranges with the whole
amount. He then chose to return six mangoes for nine oranges as both quantities
are equally priced. What is the price of each Mango?
(A)
0.4
(B)
0.45
(C)
0.5
(D)
0.55
(E)
0.6
Since 6 mangoes are returnable for 9 oranges,
if each mango costs m and each orange costs n, then 6m = 9n,
or 2m = 3n. Solving for n yields, n = 2m/3.
Now, since 50 mangoes and 30 oranges together cost 42 dollars,
50m
+ 30n = 42
50m
+ 30(2m/3) = 42
m(50 + 30 × 2/3) = 42
m(50 + 20) = 42
70m
= 42
m = 42/70 = 6/10 = 0.6
The
answer is (E).
5.
A ship is sinking and 120 more tons of water would suffice to sink it. Water
seeps in at a constant rate of 2 tons a minute while pumps remove it at a rate
of 1.75 tons a minute. How much time in minutes has the ship to reach the shore
before is sinks?
(A)
480
(B)
560
(C)
620
(D)
680
(E)
720
We have that water enters the ship at 2 tons
per minute and the pumps remove the water at 1.75 tons per minute. Hence, the
effective rate at which water is entering the ship is 2 – 1.75 = 0.25 tons per
minute.
Since
it takes an additional 120 tons of water to sink the ship, the time left is
(120 tons)/(0.25 tons per minute) = 120/0.25 = 480 minutes. The answer is (A).
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