How many gallons in swimming pool 15'x30'x6'?

Answer 1

There are approximately 20,200 US gallons in a 100 cubic yard swimming pool. I think a more accurate answer would be in the naighborhood of 17,000 gal length x width x times the average depth ( 6 + 3 =9 divided by 2 = 5) x 7.4

Answer 2

Length x width x average depth x multiplier

Length: 32

Width: 15

Average depth: ((6+3)/2) = 4.5

Multiplier: 7.5

15 x 32 x 4.5 x 7.5 = 16200