$A$ pipe fills a water tank three times faster than another pipe. If the two pipes together can fill the empty tank in $36$ $minutes$,then how much time will the slower pipe alone take to fill the tank?

Two pipes $A$ and $B$ can fill a tank in $30$ $minutes$ and $45$ $minutes$ respectively. Pipe $C$ can empty the tank in $36$ $minutes$. Initially,pipes $A$ and $B$ are opened. After $12$ $minutes$,pipe $C$ is also opened. What is the total time (in $minutes$) required to fill the tank?

$A$ pipe can fill a tank with water in $5$ $hours$ and another pipe can empty the same tank in $4$ $hours$. If the tank is completely filled and both the taps are opened together,in how much time $(hours)$ will the tank be empty?

Two pipes $A$ and $B$ can fill a water tank in $10$ and $12$ $min,$ respectively,and a third pipe $C$ can empty it at the rate of $6$ $gallons$ per $min.$ If $A, B,$ and $C$ are opened together,they fill the tank in $20$ $min.$ What is the capacity (in $gallons$) of the tank?

Three pipes $A, B$ and $C$ can fill a tank in $6$ hours. After working together for $2$ hours,$C$ is closed and $A$ and $B$ fill the remaining part in $7$ hours. The number of hours taken by $C$ alone to fill the tank is:

Pipe $A$ can fill a cistern in $6 \, h$ and pipe $B$ can fill it in $8 \, h$. Both the pipes are opened simultaneously,but after $2 \, h$ pipe $A$ is closed. How many hours will $B$ take to fill the remaining part of the cistern?