Question 521376
a water tank is connected to two pumps. it takes 40 mins to fill the water tank from the pump at the top, and 60 mins to empty it using the pump at the bottom. if we pump water at the same time as pumping water out, what fraction of the tank will be filled in 1 minute?
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1/40=rate of fill pump
1/60=rate of drain pump
After 1 minute:
1/40-1/60=3/120-2/120=1/120
ans:
1/120 of the tank will be filled after one minute