Which calculation provides the volume of water in a circular pool?

The calculation that provides the volume of water in a circular pool involves multiplying the area of the pool's surface by the average depth of the water. Since the pool is circular, the area can be determined using the formula for the area of a circle, which is pi multiplied by the radius squared.

The full volume formula is:

Volume = Area of the circle * Average Depth

Here, the area of the pool can be rewritten as:

Area = Pi * (Diameter / 2)²

When you include the average depth, the formula for calculating the volume transforms into:

Volume = Pi * (Diameter / 2)² * Average Depth

Converting diameter to radius allows for a streamlined calculation, but since the question is framed with diameter and average depth, the option that uses the diameter directly is more straightforward and consistent. The adjustment from cubic feet to gallons (7.48 gallons per cubic foot) is also appropriate when the volume needs to be expressed in gallons, which is commonly used in pool management.

This option effectively incorporates all necessary components to arrive at an accurate volume calculation for water in a circular pool, thereby confirming its correctness.