A leak in the bottom of a tank can empty the full tank in 6 hours. An inlet pipe fills water at the rate of 4 liters a minute. When the tank is full, the inlet is opened and due to the leak the tank is empty in 8 hours. The capacity of the tank (in liters) is

A. 5260   
B. 5846
C. 5760   
D. 6970
Answer:     C

Explanation:     

Work done by the inlet in 1 hour = (1/6) - (1/8) = 1/24
Work done by the inlet in 1 min = (1/24) * (1/60) = 1/1440
Volume of 1/1440 part = 4 liters.
Volume of whole = (1440 * 4) liters = 5760 liters.