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Question
The radius and height of a cylinder, a cone and a sphere are same. Calculate the ratio of their volumes.
Solution
Let r, h be the radius and height of Cylinder, Cone and Sphere.
Volume of cylinder = `pir^2h`
Volume of sphere = `4/3pir^3` (h = 2r for sphere)
Volume of cone = `1/3pir^2h`
`pir^2h : 1/3pir^2h : 4/3pir^3`
The volume of a cylinder is three times the volume of a cone with equal height and radius. The volume of a sphere is two times the volume of a cone with equal height and radius.
So the ratio of volumes is 3 : 1 : 2.
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