Quandaries and Queries


    Would you be so kind as to help me with a problem? My memory has failed me in remembering how to calculate how much liquid in gallons a tank will hold. The tank is 8 feet long and 44 inches in diameter. Your help would be greatly appreciated.
Thank you,


Hi Jim,

The volume of a cylinder is the area of the base, times the height. You have a circular base and the area of a circle is


where r is the radius and is approximately 3.1416.

A US gallon is 231 cubic inches so I would put you dimensions in inches before doing the calculations. 8 feet is 96 inches so the volume in cubic inches is

r2 height = 3.1416 222 96 = 145,971 cubic inches.

Since there are 231 cubic inches in a gallon this is

 145,971/231 = 632 gallons.



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