# Pipes and Cisterns - Aptitude Questions and Answers Part 3

11. Two pipes P and Q take 1/4 hr and 1/3 hr respectively to fill a tank. The two pipes are opened simultaneously but P is turned off after sometime. The tank takes 12 minutes to get full after this. Find the time for which Pipe P was open.

 a. 3 3 minutes 7
 b. 4 3 minutes 5
 c. 5 2 minutes 5
 d. 8 1 minutes 9

 Answer: a. 3 3 minutes 7

12. Two inlets A and B can fill a cistern in 45 and 440 minutes respectively. They were opened simultaneously but A was turned off in some time while B filled the remaining cistern alone in 23 minutes. Find the time after which inlet A was closed.

a. 7 minutes
b. 8 minutes
c. 9 minutes
d. 11 minutes

13. A tap can completely fill a tank in 16 hours. However, there is an unnoticed leakage at the bottom which makes the tank fill up in 24 hours. How long will the leakage take to completely empty a full tank?

a. 36 hours
b. 42 hours
c. 44 hours
d. 48 hours

14. Tap A and B can fill a pool together in 4 hours. If opened alone, B would take 6 hours more than A to fill the pool. How long will A take to fill the pool alone?

a. 1 hour
b. 2 hours
c. 6 hours
d. 8 hours

15. Consider the following:

i. There are three pipes to fill a tank.
ii. Time taken by Pipe 1 and Pipe 2 together to fill the tank is equal to the time taken by Pipe 3 alone.
iii. Pipe 2 alone takes 5 hours less than Pipe 1 and 4 hours more than Pipe 3.

How much time would Pipe 1 take to fill the tank alone?

a. 6 hours
b. 10 hours
c. 15 hours
d. 30 hours