Question

A piece can fill a tank in $12$ hours. By mistake, a waste pipe at the bottom is left opened and the tank is filled in $16$ hours. If the tank is full, how much time will the waste pipe take to empty it?

Answer 1

Given the the pipe can fill tank without any leak in $12hrs$

Work done without leaak $1hour=\frac{1}{12}$

Given that the waste pipe can fill a tank with leak in $1$ hour$=\frac{1}{16}$

Now, workdone by leak in $1hour=\frac{1}{12}-\frac{1}{16}$

$=>\frac{1}{48}$

So, that the total time talen to empty $=48hours$