Use the formula for Volume of Cylinder:
V = π r² h
where:
π = 3.14
r (radius) = 1/2 (diameter), if diameter is given
= 1/2 (15 feet)
= 7.5 feet
height = 6 feet
V = (3.14) (7.5 ft)² (6 ft)
= (3.14) (56.25 ft²) (6 ft)
= 1,059.75 ft³
The pool can hold 1,059.75 cubic feet of water.