Two pipes A and B can fill a cistern in `37(1/2)` and 45 min, respectively. Both pipes are opened. The cistern will be filled in just half an hour, if pipe B is turned off after (a) 5 min

If two pipes A and B can fill a tank in 20 and 30 min separately. If both pipes are opened, then tank will be filled in

Two pipes A and B can fill acistern in 15 and 20min, respectively. Both the pipes are opened together, but after 2 min, pipeAis turned off. What is the total time required to fill the tank?

Two pipes A and B can fill a tank in 15 minutes and 20 minutes respectively. Both the pipes are opened together but after 4 minutes, pipe A is turned off. What is the total time required to fill the tank?

Two pipes, A and B, can fill an empty cistern in 20min and 40min, respectively. Both the pipes are opened together, and after some time, pipe A is closed. If the cistern gets filled in 30 min, then for how long was pipe A kept open?