1.  A pump can fill a tank with water in 2 hours. Because of a leak, it took 2 hours to fill the tank. The leak can drain all the water of the tank in:
A. 4(1/3) hours
B. 7 hours
C. 8 hours
D. 14 hours

Answer: Option D

Explanation:

Work done by the leak in 1 hour = 1 - 3 = 1 .
2 7 14

Leak will empty the tank in 14 hrs.