Q20 of 47 Page 1

A right circular cone of radius 3 cm, has a curved surface area of 47.1 cm2. Find the volume of the cone.

It is given to the question that,

Radius of right circular cone = 3 cm


Curved surface area of cone = 47.1


πrl=47.1


3.14 × 3 × l=47.1


∴ l = 5 cm


By using Pythagoras theorem, we have


r2 + h2 = l2


(3)2 + h2 = (5)2


h2 = 16


h= �4


We know that,



=


= 37.68 cm3


Hence, the volume of cone is 37.68 cm3


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