A tap can fill a tank in 5½hours. Because of a leak, it took 8 1/4 hours to fill the tank. In how much time (in hours) will the leak alone empty 30% of the tank?

A tap can fill a tank in 5½hours. Because of a leak, it…

A tap can fill a tank in 5½hours. Because of a leak, it took 8 $\frac{1}{4}$ hours to fill the tank. In how much time (in hours) will the leak alone empty 30% of the tank?

Show answer & explanation

Correct answer: D

Explanation

The correct answer is option 4 i.e. $\frac{99}{20}$

A tap can fill a tank in 5½hours = 11/2 hours

Let the efficiency of A = 2 units per hour

Then the total work = 11/2 × 2 = 11 units.

Due to a leak, it takes = 33/4 hours.

Let the efficiency of a leak be x unit per hour

(2 - x) × 33/4 = 11

x = 2/3

30% of work = 11 × 30% = 3.3 units

Times taken by a leak to empty the tank = 3.3/(2/3) = 99/20.

SSC CGL 2022 PYQ — Question 32