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 Question From Genevieve: We have a pile of dirt approximately 6 feet high by 15 feet wide by 80 feet long. We need to know how many cubic yards of dirt are in this pile. Thank you

Hi Genevieve,

I am going to assume that your pile of dirt is somewhat the same shape as the pile of dirt in my response to a question from Ron. If so you can use the expression that I developed there,

$V = \frac12 W \times H \times S + \frac13 \pi R^2 \times H$

where $V$ is the volume of the pile, $W$ is its width, $H$ is its height, $L$ is its length and $R = \large \frac{W}{2},$ where $S = L - W.$ In your case $W = 15$ feet, $H = 6$ feet, $L = 80$ feet, $W = 80 - 15 = 65$ feet, and $R = \large \frac{65}{2}$ feet.

This will give you the volume in cubic feet. To convert to cubic yards ask Google. Type What is V cubic feet in cubic yards into the Google search window where V is the volume in cubic feet.

Please write back if my assumption about the shape of the pile is incorrect or something is not clear,
Harley

Genevieve wrote back

The dirt pile question I sent earlier -- the pile is basically a rectangle

If the pile is rectangular

then the volume is the length times the width times the height. So that's

$80 \times 15 \times 6 = 7200 \mbox{ cubic feet.}$

Again to convert to cubic yards ask Google. Type What is 7200 cubic feet in cubic yards into the Google search window.

Harley

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