Question: 24 gallons per second of water flows down a waterfall. If you have an empty basin that can hold 260 gallons of water. The basin leaks water at 4 gallons per second. how long would it take to fill the basin with water from the waterfall in seconds? Think carefully first, then make a decision:
24 gallons in minus 4 gallons out is 24 - 4 = 20 gallons per second. 260 gallons divided by 20 gallons per second 260 / 20 = 13 seconds. So the answer is 13.