Two pipes can fill a cistern in 55 min and 66 min respectively and a waste pipe can drain off 1320 gallons per minute. If all of them can fill the cistern in 2 hours, then what is the capacity of the cistern(in gallons) ? 

52800

C's efficiency = 24 +20 - 11 = 33

Time taken by C = \(\frac{1320}{33}\) = 40 min

ATQ,

In 1 minute C can fill = 1320 gallon

In 40 min C can fill = 1320 × 40 = 52800 gallon

Therefore, Capacity of tank = 52800 gallon