Pipes  A and B are emptying pipes and can empty a tank in 6 hours and 16 hours, respectively. C is a filling a pipe. All the three pipes were opened together. They took 80 minutes to empty $$ {5\over 8}th$$ of the tank. Pipe C alone can fill the tank in:

One fill pipe A takes 3 minutes more to fill the cistern than two fill pipes A and B opened together to fill it. Second fill pipe B takes $$ {21{1\over 3}}$$ minutes more to fill cistern than two fill pipes A and B opened together to fill it. When will the cistern be full if both pipes are opened simultaneously?

A tap can fill the tank in 8 hours and another can empty it in 16 hours. If both the taps are opened simultaneously, the time (in hours) to fill the tank is__.

Three pipes, A B and C, can fill a cistern in 12, 18 and 24 minutes, respectively. If all the pipes are opened together for 7 minutes, what will be the volume of the water that overflows as the percentage of the total volume of the cistern?

A pump can fill a cistern in 40 minutes and another pump can empty the filled up cistern in 1 hour. By mistake, without closing the second pump, the first pump is opened. The time in which the empty cistern will be filled up is

A tap can fill a tank in 6 hours. After half the tank is filled, three more similar taps are opened. What is the total time taken to fill the tank completely?

Pipes P and Q can fill a tank in 18 and 27 minutes, respectively, whereas Pipe R can empty the full tank in 54 minutes.  P and Q were opened together for 6 minutes and then   closed and R was opened. The tank was emptied by R alone in :

A cistern can be filled by two pipes filling separately in 12 and 16 min respectively. Both pipes are opened together for a certain time but being obstructions, only 7/8 of full quantity water flows through the former and only 5/6 through the latter pipe. The obstructions, however, being suddenly removed, the cistern is filled in 3 minutes from that moment. How long was it obstructions before the full flow began?