Question 54

An inlet pipe takes 8 hoursto fill a tank. An outlet pipe takes 12 hours to empty it. If both pipes are opened simultaneously, in how many hours will the tank be filled?

Solution

An inlet pipe takes 8 hours to fill a tank. An outlet pipe takes 12 hours to empty it.

Time taken to fill in 1 hour $$=\frac{1}{8}$$

Time taken to empty in 1 hour $$=-\frac{1}{12}$$

If both pipes are opened simultaneously tank be filled in 1 hour

$$\frac{1}{8}-\frac{1}{12} =\frac{1}{24}$$

Total time taken is 24 hours.

Option C is correct.

Create a FREE account and get: