Question
If a tank can be filled by a tap in 15 hours, but due to
an outlet, it actually takes 5 hours longer to fill the tank, find the duration in which the outlet alone would empty the tank?Solution
Let tap ‘A’ fill the tank and tap ‘B’ empty the tank. Taking LCM of 15 and 20 = 60 Efficiency of A = 4 Efficiency of (A – B) = 3 Efficiency of B = 4 – 3 = 1 Tap B will empty the tank = 60/1 = 60 So, tap B will empty the tank in 60 hours.
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