area of a circle equals pi * radius so 3.14 * 9ft * 9ft = 254.34 square ft. 254.34 square ft * 4 ft deep = 1017.36 cubic ft. since there are 7.48 gallons in 1 cubic ft of water, multiply
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There are 7.48051948 US gallons per cubic foot, and the pool is
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You work out the volume of water in cubic feet first, 18 x 9 x 4 = 648 cubic feet. In the USA there are 7.48052 US gallons in a cubic foot x 648 = 4847.38 US Gallons (app. In the
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Your 18ft around pool is 4 feet deep, which makes it a cylinderic volume of so many cu.ft.(cubic feet) capacity. If completely filled... Vcyl = base area X height, r=18/2(pi), then
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