Three pipes A, B and C are attached to a tank. A and B can fill  it in 20 and 30 minutes respectively while C can empty it in 15 minutes. If A, B and C are kept open successively for 1 minute each how soon will the tank be filled?

Two taps A and B can fill a tank in 20 min and 30 min, respectively. An outlet pipe C can empty the full tank in 15 min A, B and C are opened alternatively ,each for 1 min . How long will the tank take to filled ?

Two pipes A and B can fill a tank in 25 min and 45 min respectively. Pipe C can empty. The tank in 10 minutes. If pipe A and pipe B are kept open for 5 minutes in The begining and then C is also opened. In what time will the tank be emptied?

Two pipes A and B can fill a tank in 100 minutes and 120 minutes respectively. Pipe C can alone empty the same tank in 200 minutes. If all three pipes are opened together, then in how many minutes will the tank be filled?

Two pipes A and B can fill a tank in 12 and 15 minutes respectively. A third pipe C can empty it in 10 minutes. How long will it take to fill in the tank if all pipes are opened simultaneously ?

Pipe A and B can fill a water tank in 30 and 45 minutes respectively while pipe C can take out all the water is 60 minutes. If the three pipes are opened simultaneously . How long it fill the empty tank