Pipes and Cistern

1.		Two pipes A and B together can fill a cistern in 4 hours. Had they been opened separately, the pipe B would have taker 6 hours more than pipe A to fill the cistern. pipe A can fill the cistern separately in:

1 hrs

2 hrs

6 hrs

4 hrs

2.		A pipe can fill a tank three times as fast as the other pipe. If together the two pipes can fill the tank in 36 minutes, then the slower pipe alone can fill the tank in:

120 min

136 min

144 min

150 min

3.		Two pipes A and B can separately fill a cistern in 60 minutes and 75 minutes respectively. There is a third pipe in the bottom of the cistern to empty it. If all the three pipes are opened simultaneously then the cistern is filled in 50 minutes. The third pipe alone can empty the cistern in:

90 min

100 min

110 min

120 min

4.		Two pipes, A and B, can fill a tank in 60 minutes and 40 minutes respectively. How many minutes will it take to fill the tank from empty state if pipe B is used for half the time and pipe A and pipe B fill it together for the other half ?

20 min

25 min

27 min

30 min

5.		Two pipes A and B can fill a tank in 12 minutes and 15 minutes respectively. If both the pipes are opened simultaneously, and the pipe A is closed after 3 minutes, then how much more time will it take to fill the tank by pipe B ?

7 min 15 sec

7 min 45 sec

8 min 15 sec

8 min 45 sec

6.		Two pipes A and B can fill a tank in 15 hours and 20 hours respectively while a third pipe C can empty the full tank in 25 hours. All the three pipes are opened in the beginning but after 10 hours, pipe C is closed. In how much time, the tank will be filled ?

12 hrs

13 hrs

14 hrs

15 hrs

7.		Two pipes A and B can fill a cistern in 12 minutes and 15 minutes respectively while a third pipe C can empty the filled tank in 6 minutes. Pipe A and pipe B are kept open for 5 minutes in the beginning and then pipe C is also opened. In what time the cistern will be emptied ?

30 min

33 1/3 min

40 min

45 min

8.		A tank is filled in 5 hours by three pipes A, B and C. The pipe C is twice as fast as B and B is twice as fast as A. How much time will pipe A alone take to fill the tank?

30 hours

32 hours

35 hours

40 hours

9.		Two pipes A and B can fill a tank in 36 min and 45 min respectively. A pipe C can empty the full tank in 30 min. First A and B are opened and after 7 minutes, pipe C is also opened. In how much time, the tank will be full ?

46 min

48 min

50 min

52 min

10.		A pump can fill a tank in 2 hours but due to a leak, it took 2 1/3 hours to fill the tank. The leak can empty the tank in:

13 1/3 hours

10 hours

12 hours

14 hours