Pipes and Cisterns Exercise Problems

1. Pipe A can fill a tank in 5 hours, pipe B in 10 hours and pipe C in 30 hours. If all the pipes are open,in how many hours will the tank be filled ?
A.  2   
B.  2.5
C.  3   
D.  3.5
Explanation :

2. Three pipes A, B and C can fill a tank from empty to full in 30 minutes, 20 minutes and 10 minutes respectively. When the tank is empty, all the three pipes are opened. A, B and C discharge chemical solutions P, Q and R respectively. What is the proportion of solution R in the liquid in the tank after 3 minutes ?
A.  5/11
B.  6/11
C.  7/11
D.  8/11
Explanation :

3. Two taps A and B can fill a tank in 5 hours and 20 hours respectively. If both the taps are open then due to a leakage, it took 30 minutes more to fill the tank. If the tank is full, how long will it take for the leakage alone to empty the tank ?
A.  8 hrs
B.  9 hrs
C.  18 hrs
D.  36 hrs
Explanation :

4.  12 buckets of water fill a tank when the capacity of each bucket is 13.5 liters. How many buckets will be needed to fill the same tank, if the capacity of each bucket is 9 liters?
A. 8   
B. 15
C. 16   
D. 18
Explanation :

5. One tap can fill a cistern in 2 hours and another tap can empty the cistern in 3 hours. How long will they take to fill the cistern if both the taps are opened ?
A. 5 hrs   
B. 7 hrs
C. 6 hrs   
D. 8 hrs
Explanation :

6. A tap can fill a tank in 16 minutes and another can empty it in8 minutes. If the tank is already half full and both the tanks are oped together, the tank will be:
A. filled in 12 min   
B. filled in 8 min
C. emptied in 12 min   
D. emptied in 8 min
Explanation :

7. Two pipes A and B can fill a cistern in 12 minutes and 16 minutes respectively. If both the pipes are opened together, then after how much time B should be closed so that the tank is full in 9 minutes ?
A. 3 min and 30 sec.   
B. 4 min and 30 sec.
C. 4 min.   
D. 4 min 77 sec.
Explanation :

8. A tank can be filled by a tap in 20 minutes and by another tap in 6O minutes. Both the taps are kept open for 10 minutes and then the first tap is shut off. After this, the tank will be completely filled in:
A. 10 min   
B. 15 min
C. 12 min   
D. 20 min
Explanation :

9. A leak in the bottom of a tank can empty the full tank in 6 hours. An inlet pipe fills water at the rate of 4 liters a minute. When the tank is full, the inlet is opened and due to the leak the tank is empty in 8 hours. The capacity of the tank (in liters) is
A. 5260   
B. 5846
C. 5760   
D. 6970
Explanation :

10. 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
Explanation :

11.  An electric pump can fill a tank in 3 hours. Because of a leak in the tank, it took 3 hours 30 min to fill the tank. The leak can drain out all the water of the tank in :
A. 10 hours 30 min   
B. 21 hours
C. 12 hours   
D. 24 hours
Explanation :

12. 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
Explanation :

13. A cistern can be filled by a tap in 4 hours while it can be emptied by another tap in 9 hours. If both the taps are opened simultaneously, then after how much time will the cistern get filled?
A. 4.5 hrs
B. 6.5 hrs
C. 5 hrs
D. 7.2 hrs
Explanation :