Q9 of 51 Page 1

If the heights of two right circular cones are in the ratio 1:2 and the perimeters of their bases are in ratio 3:4, what is the ratio of their volumes?

The ratio of their volumes is 9:32.

Given: heights are in ratio 1:2


Perimeters of bases are in ratio 3:4


Formula Used:


The volume of cone =


Explanation:



Let height be H and h


Radius be R and r


Acc. to question,



⇒ h = 2H


As the bases are circular,


The perimeter of base = 2πr


Acc. to question,





Now,







Hence, the ratio of their volumes is 9:32.


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