Question Bank: Pipe & Cistern

A pipe can fill a tank in 6 hours, and another pipe can fill the same tank in 9 hours. If both pipes are opened together, how long will it take to fill the tank?

a) 3.6 hours
b) 4 hours
c) 5 hours
d) 3 hours
Two pipes A and B can fill a tank in 20 minutes and 30 minutes respectively. If both are opened together, how long will it take to fill the tank?

a) 12 minutes
b) 15 minutes
c) 25 minutes
d) 10 minutes
A pipe can fill a tank in 12 hours and another can empty it in 8 hours. How long will it take to fill the tank if both pipes are open?

a) 24 hours
b) 48 hours
c) 30 hours
d) 36 hours
A cistern has two inlets, A and B, which can fill it in 12 minutes and 15 minutes respectively. There is also an outlet C which can empty it in 20 minutes. If all three are opened together, how long will it take to fill the cistern?

a) 8 minutes
b) 10 minutes
c) 12 minutes
d) 15 minutes
Three pipes A, B, and C can fill a tank in 10 hours, 12 hours, and 15 hours respectively. If A, B, and C are opened for 2 hours each, how much of the tank will be filled?

a) 2/5
b) 1/2
c) 3/5
d) 7/15
Two pipes A and B can fill a tank in 16 minutes and 24 minutes respectively. If both pipes are opened together, how much time will it take to fill the tank?

a) 8 minutes
b) 9.6 minutes
c) 10.5 minutes
d) 11.2 minutes
A pipe can fill a cistern in 10 hours, and another pipe can empty it in 15 hours. If both pipes are opened together, how much time will it take to fill the cistern?

a) 30 hours
b) 45 hours
c) 60 hours
d) 90 hours
Two pipes A and B can fill a cistern in 14 hours and 21 hours respectively. A third pipe C can empty the cistern in 42 hours. If all three pipes are opened, in how much time will the cistern be filled?

a) 18 hours
b) 24 hours
c) 30 hours
d) 42 hours
A cistern is normally filled in 9 hours but takes 10 hours due to a leak. How long will the leak take to empty the full cistern?

a) 90 hours
b) 80 hours
c) 85 hours
d) 72 hours
A pipe can fill a tank in 18 hours. Due to a leak, it takes 24 hours to fill the tank. How long will the leak take to empty the full tank?

a) 72 hours
b) 108 hours
c) 96 hours
d) 120 hours
Two pipes A and B can fill a tank in 20 minutes and 60 minutes respectively. If both are opened together, how long will it take to fill the tank?

a) 12 minutes
b) 15 minutes
c) 16 minutes
d) 18 minutes
Pipes A, B, and C can fill a tank in 12 hours, 15 hours, and 20 hours, respectively. If all three pipes are opened together, how long will it take to fill the tank?

a) 5 hours
b) 6 hours
c) 4 hours
d) 8 hours
Pipes A and B can fill a tank in 10 hours and 15 hours, respectively. Pipe C can empty the tank in 30 hours. If all three pipes are opened together, how long will it take to fill the tank?

a) 8 hours
b) 10 hours
c) 12 hours
d) 6 hours
Two pipes A and B can fill a tank in 24 minutes and 30 minutes, respectively. Pipe C can empty the tank in 40 minutes. If all three pipes are opened together, how long will it take to fill the tank?

a) 20 minutes
b) 30 minutes
c) 32 minutes
d) 28 minutes
Pipes A, B, and C can fill a tank in 6 hours, 8 hours, and 12 hours, respectively. However, Pipe C is an outlet pipe. How long will it take to fill the tank if all three pipes are opened together?

a) 5 hours
b) 4 hours
c) 3 hours
d) 6 hours