two pipes can fill a tank in 20 hours.f the ratio of capacities of the pipes are 2:3 . how much time each pipe will take to fill the tank alone
Answers
two pipes can fill a tank in 20 hours.f the ratio of capacities of the pipes are 2:3 . how much time each pipe will take to fill the tank aloneAnswer:
Time taken by pipe X to fill the tank = 20 hours
Time taken by pipe Y to fill the tank = 35 hours
Total capacity of tank = LCM of (20 and 35) = 140 units
Efficiency of pipe X = 140/20 = 7 units/hour
Efficiency of pipe Y = 140/35 = 4 units/hour
Efficiency of pipe X and Y together = 7 + 4 = 11 units/2 hours
Time taken to fill 132 units of tank = 132 × 2/11 = 24 hours
Remaining capacity = 140 - 132 = 8 units
Now its Y turn to fill.
Now Y fill 4 units in next 1 hour
Time taken to fill 136 units of tank = 24 + 1 = 25 hours
Now X fill the remaining 4 units.
Time taken by X to fill remaining 4 units = 4/7 hours
∴ Total time taken to fill the tank = 25 + 4/7 = 179/7 hours