Answer:
590.76 hours
Explanation:
A water tank holds 24,000 gallons
Two-Third of water quantity =

=
Rate of using water is 650 gallons per day
650 gallons of Water used in day = 1
650 gallons of Water used in hours= 24
1 gallon of Water used in hours=

16000 gallon of Water used in hours=

Hence It will take 590.76 hours for 2/3 of the water to be used