Question
Pipes ‘D’ and ‘E’ alone can fill a tank in 16
minutes and 24 minutes, respectively, while pipe ‘F’ can empty the same tank in 48 minutes. If all three pipes are opened together, then find the time taken to fill the tank.Solution
ATQ,
Let the capacity of the tank be 96 litres {LCM (16, 24, and 48)}
Efficiency of pipe ‘D’ = (96/16) = 6 litres/minute
Efficiency of pipe ‘E’ = (96/24) = 4 litres/minute
Efficiency of pipe ‘F’ = (96/48) = 2 litres/minute
Required time = {96 / (6 + 4 – 2)} = 12 minutes
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