Give stream of consciousness and then the final answer. Two pipes can fill a tank in 20 and 12 hours, while third pipe will make the tank empty in 20 hours. If all three pipes operate simultaneously. In how many hours the tank will be filled ?\nOptions:\n(A) 5 Hours\n(B) 7 Hours\n(C) 8 Hours\n(D) 9 Hours\n(E) 12 Hours
User
In 1 hour it fill 1/20 + 1/12 - 1/20 = 1/12\nSo fill tank fill up in 12 Hours
The final answer: (E).
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