Math CentralQuandaries & Queries


Question from Judy:

Have an area 731 sq. ft with 5" of water all the way around.  How many gallons is this?  Your help is appreciated.

Hi Judy.

Gallons is a measurement of volume, which you get when you multiply an area by a length. Let's first convert 5 inches to (5/12) of one foot. We convert to feet so that we will get a volume in cubic feet.

731 feet2 x (5/12 feet) = 304.58 feet3.

When I look up the conversion factor for cubic feet into gallons, I find it is 7.481 US gallons (if you are in part of the world that uses the larger imperial gallons, you would use 6.229 instead). So I can multiply:

304.58 feet3 x (7.481 US gallons / foot3) = 2279 US gallons.

Hope this helps,
Stephen La Rocque.

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