pool gallons 7630.2 How do you get that (D2)x(D2)x3.14 Average depth x 7.5. In your case 18x18x3.14+4x7.5= 7630.2 .
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NO! Sorry, but that lot is all wrong.
The formula for volume is wrong, and there is no addition in it either. The volume of a cylinder is pi*r^2*H (or depth here, for H), where r is the Radius.
So the volume is 3.142 x 9 x 9 x 4 =
1018.01 cubic feet (assuming 4 feet is the water depth and is constant across the pool).
Now multiply that by the number of gallons (US ones?) in 1 cu.ft. to find the water capacity.
The volume of the pool is 2,290.2 cu ft and has a maximum capacity of 17,133.2 gallons of water.
1,770 gallons.
3384 gallons for every foot deep it is.
5,287.7 gallons of water.
13,594 US gallons of water.
Three feet of water in a 12-foot round pool is about 2,550 gallons.
7,646.4 gallons are needed.
About 7,650 gallons.
The volume of the pool is 2,290.2 cu ft and has a maximum capacity of 17,133.2 gallons of water.
489.76 gallons of water.
1,770 gallons.
3384 gallons for every foot deep it is.
3,398.4 gallons.
181,248 gallons.
6,200 gallons.
5,974 gallons.
5,287.7 gallons of water.