Question

Pipe A fills a tank at the rate of 100lit/min, Pipe B fills at the rate of 25 lit/min, pipe C drains at the rate of 50 lit/min. The three pipes are kept open for one minute each, one after the other. If the capacity of the tank is 7000 liters, how long will it take to fill the tank if
279.25 mins, 280 mins and 280 mins
280 mins, 280 mins and 279.25 mins
279 mins, 280 mins and 279.25 mins
277 mins, 277 mins 45 sec and 280 mins

Answer 1

Option c is correct.....
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