Based on the fill rate, discharge rate and time given, the pond should be filled up by 9:00 a.m the next morning.
Pool capacity = 100 gallons
Initial filling rate = 5 gallons per hour
Amount of water in pool after 10 hours:
Filling rate × time
Amount of water in pool after 10 hours = 5 × 10 = 50 gallons
Discharge rate after 10 hours = 2 gallons per hour
Net filling rate = 5 gal/hr - 2gal/hr = 3 gal/hr
Amount of water filled into the po at this rate after 5 hours :
3 gal/hr × 5 hr = 15 gallons
Additional recharge = 4 gal/ hr
Net filling rate = 3gal/hr + 4 gal/hr = 7 gal/hr
Amount of Gallons left = 100 - (50 + 15) = 35 gallons
Number of hours till full = (gallons left) ÷ fill rate
Number of hours left = (35 ÷ 7) = 5 hours
Hence, the pool will be full after (10 + 5 + 5) = 20 hours
Therefore, the pond will be full at 9:00 am the next day.
