A rectangular swimming pool is 20 feet long, 10 feet wide, and 5 feet deep. What is its volume?

Volume of a rectangular prism (or box) = length × width × height = 20 × 10 × 5 = 1,000 cubic feet. Volume formulas commonly tested: Rectangular prism = L × W × H; Cube = side³; Cylinder = π × r² × h; Sphere = (4/3) × π × r³. Volume units: cubic feet (cu ft or ft³), cubic meters, gallons (1 cu ft ≈ 7.48 gallons; useful for converting pool volume to gallons of water needed). Applications: pool capacity, container volume, concrete needed, water/gas volume in a tank. Note the relationship: doubling all dimensions multiplies volume by 8 (2³); doubling just one dimension doubles the volume. For irregular shapes, find the volume by computing the volume of regular sections and summing. Practice converting between cubic feet and gallons: 1 cubic foot ≈ 7.48 gallons.