Q21 of 70 Page 21

A hemisphere of lead of radius 7 cm is cast into a right circular cone of height 49 cm. Find the radius of the base.

Volume of a hemisphere = (2/3)πr3


Volume of a right circular cone = (1/3)πr2h


Given, hemisphere of lead of radius 7 cm is cast into a right circular cone of height 49 cm



⇒ r2 = 14


⇒ r = 3.74 cm


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