31. Two taps A and B can fill a tank in 10 hours and 15 hours
respectively. If both the taps are opened
together, the tank will be full in:
A.5 hrs B.12 and 1/2 hrs
C.6 hrs D.7 and 1/2 hrs
32. To fill a cistern, pipes A, B and C take 20 minutes, 15
minutes and 12 minutes respectively. The time in minutes that the three pipes
together will take to fill the cistern, is :
A.5 B.12
C.10 D.15 and 2/3
33.
|
Two
pipes A and B together can fill a cistern in 4 hours. Had they been opened
separately, then B would have taken 6 hours more than A to fill the cistern.
How much time will be taken by A to fill the cistern separately?
|
A.
|
1 hour
|
B.
|
2 hours
|
C.
|
6 hours
|
D.
|
8 hours
|
|
34. A cistern has two taps which fill it in 12 mm. and 15 mm.
respectively. There is also a waste pipe in the cistern. When all the three are
opened, the empty cistern is full in 20 minutes. How long will the waste pipe
take to empty the full cistern ?
A.8 mm. B.12 mm.
C.10 mm. D.16 mm.
35. A leak in the bottom of a tank can empty the full tank in 8
hours. An inlet pipe fills water at the rate of 6 litres a minute. When the tank is full, the inlet is
opened and due to the leak, the tank is empty in 12 hours. How many litres does the cistern hod?
A.7580 B.8290
C.7960 D.8640
36.
|
Two
pipes A and B can fill a tank in 20 and 30 minutes respectively. If both the
pipes are used together, then how long will it take to fill the tank?
|
A.
|
12 min
|
B.
|
15 min
|
C.
|
25 min
|
D.
|
50 min
|
|
