Question

Pipe L can fill a tank in 8 hours but due to leakage at the bottom of the tank, it take 20 hours to fill the tank.In what time, the leakage will empty the fully filled tank.
1. 40/3  hours
2. 12/5 hours
3. 11/7  hours
4. 5/3 hours 

Answer 1

Correct Answer - Option 1 : 40/3  hours

Given

Pipe L can fill a tank without leakage in 8 hours

Pipe L can fill a can't with leakage in 20 hours.

Calculation

Let the leakage empty the tank in x hours.

Tank filled in 1 hour without leakage = (1/8)

Tank empty in 1 hour due to leakage = (1/x)

Tank filled in 1 hour with leakage = (1/20)

According to question

Tank filled in 1 hour with leakage = Tank filled in 1 hour without leakage - Tank empty in 1 hour with leakage

(1/20)= (1/8) - (1/x)

⇒ (1/x) = (1/8) - (1/20)

⇒ (1/x) = (5 - 2)/40

⇒ (1/x) = 3/40

⇒ x = 40/3 

∴ Tank empty in 40/3 hours due to leakage.