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 Question from Steven, a parent: I know a couple of formulas for determining concrete volume in cu. yd. the one I use most frequently is length in feet x width in feet x thickness in inch. Divided by 324. It works every time. Where does the number 324 come from.

Hi Steven,

There are 3 feet in a yard so to convert your measurement of the length in feet to yards you need to divide by 3. Similarly to convert the width in feet to yards you need to divide by 3. There are 36 inches in a yard so to convert the thickness in inches to yards you need to divide by 36. Thus, in totally, you need to divide by $3 \times 3 \times 36 = 324.$

Penny

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