One tap can fill a cistern in $2$ hours and another can empty the cistern in $3$ hours. How long will it take to fill the cistern if both the taps are opened (in $\text{hours}$)?

An outlet pipe can empty a cistern in $3$ $h$. In what time (in $h$) will the pipe empty two-third part of the cistern?

An inlet pipe fills $\frac{1}{8}$ part of a tank in $1 \ h$. How much time (in $h$) will the pipe take to fill the empty tank?

If a pipe fills a tank in $6 \ h$,then what part of the tank will the pipe fill in $1 \ h$?

Pipe $A$ can fill a tank in $30$ minutes,while pipe $B$ can fill the same tank in $10$ minutes and pipe $C$ can empty the full tank in $40$ minutes. If all the pipes are opened together,how much time will be needed to make the tank full?

There are two taps $A$ and $B$ to fill up a water tank. The tank can be filled in $40$ $min,$ if both taps are on. The same tank can be filled in $60$ $min,$ if tap $A$ alone is on. How much time (in $minutes$) will tap $B$ alone take to fill up the same tank?