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Find the volume of a cube whose edge length equals nine centimeters.
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So, let’s imagine we have our cube.
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Since it’s a cube, we know that every length will be the same.
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In this case, they’ll all be nine centimeters long.
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To find the volume of a cube, we multiply the length times the width times the height.
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And since all the lengths are the same, we can say that this is the length times the length times the length.
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Here, we have the volume equals nine times nine times nine.
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For our first nine times nine, we can think of this in the same way as finding the area of the front face.
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If we thought of these as individual one-centimeter cubes, we could say there’d be nine along the bottom and nine up, which would give us 81 cubes in the front face.
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And then, we know that we’d have to have nine separate rows of these 81 cubes.
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So, in our volume calculation, we would continue by 81 times nine.
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And we can evaluate that as 729.
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When it comes to our units then, since we’re working with centimeters here with our length of nine centimeters, our volume units won’t just be centimeters.
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They must be cubic centimeters for the volume.
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So, the volume of our cube is 729 cubic centimeters.