Advertisement

### Question

A city tanker is filled by two large pipes, X and Y, together in 24 and 16 minutes respectively. On a certain day, pipe Y is used for first half of the time, and both X and Y are used for the second half. How many minutes does it take to fill the tank?

**A**

12 mins.

**B**

13 mins.

**C**

11 mins.

**D**

14 mins.

**Soln.**

**Ans: a**

Let the time taken be x. Y is running for x mins, and X for x/2. So $(x/16 + x/{2 × 24})$ = 1. Solving for x, we get x = 12 mins.