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 Question from Brett, a student: I am studying for my builders license and I am having trouble figuring out cubic yards of concrete in a footing. My question that I am having trouble with is. You need to pour an 8"x16" footing that is 100ft. long. At a cost of $65 per cubic yard, how much will this cost? (A)$205 or less (B) more than $205, but less than$220 (C) $220 to$235(D) more than $235 The answer they give is (B) I keep coming up with$240.75

Hi Brett,

I would convert all the dimensions to yards first so that the resulting volume calculation is in cubic yards.

8" = 8/36 yards
16" = 16/36 yards
100 feet = 100/3 yards.

Thus the volume is

(8/36) × (16/36) × (100/3) = 3.29 cubic yards.

At $65 per cubic yards that's 3.29 ×$65 = \$213.99

I hope this helps,
Penny

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