Three taps A, B and C can fill tank in 12,15 and 20 hours respectively. If A is open all the time and B and C are open for one hour each alternately, the tank will be full ins `6\ h r s` b. `7\ h r s` c.`\ 6 2/3h r s` d. `7 1/2h r s`

Three taps A, B and C can fill a tank in 12, 15 and 20 hours respectively. If A is open all the time and B and C are open for one hour each alternatively, the tank will be full in

Two pipes can fill a tank in 20 hours and 12 hours respectively pipe C can empty that tank in 15 hours. Of B is open all the time and A and C are open for one hour each alternately. Then the tank will be full in?

Three taps A, B and C can fill a tank in 20, 30 and 36 hours respectively. If all the taps are opened together, then in how many hours will the tank be filled?

Pipes A and B can fill a tank in 5 and 6 h, respectively. Pipe C can fill it in 30 h. If all the three pipes are opened together, then in how much time the tank will be filled in?

Two pipes A and B can fill a tank in 6 hours and 4 hours respectively . If they are opened on alternate hours and if pipe A is opened first , in how many hours , the tank shall be full ?

A pipe can fill a tank in 3 hours. There are two outlet pipes from the tank which can empty it in 7 and 10 hours respectively. If all the three pipes are opened simultaneously, then the tank will be filled in 8 hou r s b. 9 hou r s c. 10 hou r s d. 11 hou r s