How much more gallons did Monday have compared to Saturday?

To determine how much more gallons Monday had compared to Saturday, one would need to analyze the specific gallon amounts for each day. If Monday's total gallons are 1,500 gallons more than that of Saturday, then the answer reflects a straightforward subtraction of Saturday's total from Monday's total.

When comparing Friday's total to Saturday's total, the difference must also be accounted for accurately to arrive at Monday's total. The calculation can be represented as:

Monday's gallons - Saturday's gallons = Difference

If this calculated difference equals 1,500 gallons, then that value indicates how much more Monday had compared to Saturday.

This approach effectively demonstrates that the selected answer is based on a clear understanding of day-to-day gallon comparisons within the context of water system management. Knowing how to compute these differences is essential for effective water resource management and for making informed decisions related to water supply on different days.