An inlet pipe fills 1/8 part of a tank in 1 h. How much time will the pipe take to fill the empty tank?

We know that, when a pipe fills 1/m part of a tank in 1 h, then the pipe takes m h to fill the tank.
Here, 1/m = 1/8 ⇒ m = 8
∴ Required time to fill the tank = 8 h