Q14 of 24 Page 227

The height of a right circular cone is 12cm. and its volume is 100 π cm3. Let us write the length of the radius of the cone.

Let, radius = r cm


Height = 12 cm


According to problem,


⇒π × r2 × 12 = 100π


⇒ 12r2 = 100


⇒ r2 = 25/3


⇒ r = 2.89


∴ Length of radius of the cone = 2.89 cm


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