How much does 2.5 gallons of water weigh?

To determine the weight of 2.5 gallons of water, we can use the fact that water has a standard weight of approximately 8.34 pounds per gallon. By multiplying the weight of water per gallon by the total number of gallons, we can find the total weight:

Weight = 8.34 pounds/gallon × 2.5 gallons = 20.85 pounds.

Therefore, when rounding to the nearest pound, this results in approximately 20.8 pounds. This calculation aligns with common knowledge about the weight of water, providing a logical basis for understanding that the weight of a specific volume of water can be easily calculated and verified.