RRB NTPC · Question 84
A tap can fill a tank in 20 minutes. If a leakage is capable of emptying the tank in 60 minutes, the tank will be filled in
Show answer & explanation
Answer: (C) 30 minutes
Explanation
The tap fills 1/20 of the tank per minute and the leak empties 1/60. Net filling = 1/20 − 1/60 = 2/60 = 1/30 per minute, so the tank fills in 30 minutes.