Pipe A can fill a tank in 4 hours, then time taken by it to fill 3/4th part of the tank is ……………

Two pipes A and B can fill a tank in 6 hours and 3 hours respectively.Both the pipes are opened simultaneously and pipe A is closed after 1hours.Find the time taken by B to fill the remaining part of the tank (in hours).

If a pipe can fill a tank in x hours: then part filled in 1 hour.

If A & B two pipes can fill a tank in 10 hr. when 'A' pipe can fill a tank in 6 hr. alone then in how much time will be taken to fill/empty the tank when pipes 'B' open alone ?

A pipe Can fill a tanke in 10 hours. The other pipe can fill a tank in 15 hours. How much time will they take to fill that tank together.