Question
The ratio of the rate of filling of two taps A and B is
3:2, respectively. If working together they can fill 3/4 of a tank in 18 minutes, how long will tap A alone take to fill the tank?Solution
ATQ, Let the rate of filling of taps A and B be ‘3a’ units per minute and ‘2a’ units per minute, respectively. 
Total capacity of tank = 24 × (3a + 2a) = 24 × 5a = 120a units Required time taken by tap A = 120a/3a = 40 minutes
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