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?

Two pipes A and B can fill a tank in 3 hours and 5 hours. Then, if all three are open, the tank is filled in 30 hours. Find in how many hours a third pipe will empty the tank?

Water flows in to a tank 15 m.×10 m. through a rectangular pipe 2 m.×1.5 m. at 20 km./hr. In how much time will the water level in the tank rise by 3m.?

A pipe can fill a tank in x hours and an another can empty it in y hours. In how many hours will they together fill it. If y>x?

Water flows into a tank which is 200 m long and 150 m wide, through a pipe of cross-section (0.3m x 0.2m) at 20 km/h. In what time will the water level be 8 m?

Two pipes, A and B, can fill a tank in X minutes and 6 minutes, respectively. If both the pipes are used together, then they take 1.5 minute to fill the tank. Find the value of X.

A pipe can fill a tank in 72 minutes. But there is a leak in the bottom of the tank due to which the tank is filled in 18 minutes more. Find in how many hours the leak can empty a full tank ?

Pipes A and B together can fill a tank in 16 hours, whereas pipe C alone can empty the full tank in 24 hours. A and B were opened together for 10 hours and then closed. Pipe C was then opened. The tank will now be emptied by C in: