Radius of a cylinder from volume and height
This math skill teaches how to determine the radius of a cylinder given its volume and height. Using the formula for the volume of a cylinder (volume = area of base × height), you rearrange the equation to find the base area first. Then, equate the base area to the formula for the area of a circle to solve for the radius.
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Find the radius of this cylinder from it's volume and its height
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The volume of any prism, including a cylinder, is just the area of its base times the length of the straight sides. In this case the straight sides are its height
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We know the volume is 36 pi, and the height is 4
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So we can rearrange and find the area of the base is 9 pi
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The area of a circle is pi times the radius squared, so we can equate that to 9 pi
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Cancelling out the factors of pi, we can see that the radius squared is 9
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So the radius must be 3
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Radius of a cylinder from volume and height
Test your understanding of radius of a cylinder from volume by practicing it! Work through the below exercises to use it in practice.