Some question: Two pipes can fill a tank in 20 and 24 minutes respectively and a waste pipe can empty 6 gallons per minute. All the three pipes working together can fill the tank in 15 minutes. The capacity of the tank is?\nOptions:\n(A) 60 gallons\n(B) 100 gallons\n(C) 240 gallons\n(D) 180 gallons\n(E) 130 gallons
Some stream of consciousness:
User
Work done by the waste pipe in 1 minute = 1/15 - (1/20 + 1/24) = - 1/40\nVolume of 1/40 part = 6 gallons\\nVolume of whole = 6 * 40 = 240 gallons. The answer: (C).
Assistant