Question
Pipe A alone fills a tank in 18 hours. Pipes A and B
together fill it in 9 hours. Pipes B and C together fill it in 6 hours. Find the time taken by A, B and C together to fill the tank.Solution
ATQ, A = 1/18 B = 1/9 − 1/18 B = (2 − 1)/18 = 1/18 B + C = 1/6 C = 1/6 − 1/18 C = (3 − 1)/18 = 2/18 = 1/9 A + B + C = 1/18 + 1/18 + 1/9 = (1 + 1 + 2)/18 = 4/18 Required time = 18/4 hours = 9/2 hours
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