Question
A single tap takes 8 hours to fill the entire tank.
Initially, only one tap is open, and it fills one-fourth of the tank. At that point, three additional identical taps are turned on. How much total time is required to completely fill the tank?Solution
ATQ,
The first tap alone fills one-fourth of the tank in 8/4 = 2 hours.
With 4 taps running, the remaining three-fourths is filled in (3/4) × (8/4) = 3 hours.
Total time = 2 + 3 = 5 hours.
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