Q8 of 63 Page 20

If the radius of the base of a cone is halved, keeping the height same, what is the ratio of the volume of the reduced cone to that of the original cone?

Let r be the radius of the base and h be the height of the original cone. Then,



Let V2 be the volume of the reduces cone. Then,




Hence ratio of reduce cone to original cone = 1:4


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