35. A leak in the bottom of a tank can empty the full tank in 8 hours. An inlet pipe fills water at the rate of 6 litres a minute. When the tank is full, the inlet is opened and due to the leak, the tank is empty in 12 hours. How many litres does the cistern hod?
A.7580 B.8290
C.7960 D.8640
Answer: 8640
Explanation: Work done by the inlet in 1 hour = (1/8) - (1/12) = 1/24
Work done by the inlet in 1 min = (1/24) * (1/60) = 1/1440
Volume of 1/1440 part = 6 litres
Volume of whole = (1440 x 6) litres 8640 litres.
