If two pipes function together,the tank will be filled in $12$ $h$. One pipe fills the tank $10$ $h$ faster than the other. How many $h$ does the faster pipe take to fill up the tank?

If two pipes function simultaneously,the reservoir will be filled in $12$ $hours$. One pipe fills the reservoir $10$ $hours$ faster than the other. How many $hours$ does the faster pipe take to fill the reservoir?

Three pipes $A, B$ and $C$ can fill a cistern in $10$ $hours$,$12$ $hours$ and $15$ $hours$ respectively. First $A$ was opened. After $1$ $hour$,$B$ was opened and after $2$ $hours$ from the start of $A$,$C$ was also opened. Find the time in which the cistern is just full.

Pipe $A$ can fill a tank in $5$ $hours$,pipe $B$ in $10$ $hours$,and pipe $C$ in $30$ $hours$. If all the pipes are opened,in how many $hours$ will the tank be filled?

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?

Pipe $X$ can fill a tank in $20$ $hours$ and pipe $Y$ can fill the tank in $35$ $hours.$ Both the pipes are opened on alternate hours. Pipe $Y$ is opened first,then in how much time (in hours) will the tank be full?