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Measurement Frequently Asked Questions (FAQ)

Calculate the Capacity of a Tank

How do I figure out the capacity in gallons of a fuel (or water or oil) tank?  The tank resembles the tank on a tanker truck or railroad tanker car.  The oval end is X feet tall by Y feet wide, and the tank is Z feet long.

You first need to find the capacity in cubic feet of the tank, then use ConvertIt to convert that measurement to gallons (or liters, etc.).  To calculate its capacity, take the height of the tank, divide by two, multiply by the width of the tank, divide by two, multiply by pi (which is 3.1415923...), and multiply by the length of the tank.  (Make sure that the height, width, and length of the tank are all expressed in the same units, such as feet or meters.)  For example, assume that the tank is 4 feet wide, 3 feet tall, and 8 feet long.  The calculation is 4 / 2 * 3 / 2 * 3.1415923 * 8 = 75.398224 cubic feet.  Use ConvertIt to Convert From 75.398224 cubic feet to gallons and the result is 564.017883 gallons.

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