Suppose A, B and C are three taps fixed to the bottom of a tank with draining capacity 1 : 2 : 3. When all three of them are on, it takes 1 hour to drain out the full tank. If A and C are on but B is off, then how much time, in minutes, will it take to em

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Q: 91 (CAPF/2023)
Suppose A, B and C are three taps fixed to the bottom of a tank with draining capacity 1 : 2 : 3. When all three of them are on, it takes 1 hour to drain out the full tank. If A and C are on but B is off, then how much time, in minutes, will it take to empty out a full tank of water?
(a) 75
(b) 90
(c) 105
(d) 120

question_subject: 

Science

question_exam: 

CAPF

When all taps are on, the total draining capacity is 1/unit time. If only A and C are on, we must find the combined rate without B. Solving the rates, A and C together would take 90 minutes.