Q12 of 52 Page 1

A solid sphere of radius 10.5 cm is melted and recast into smaller solid cones, each of radius 3.5 cm and height 3 cm. Find the number of cones so formed. [Use π = 22/7]

Radius of the sphere = 10.5 = 21/2 cm


Volume of the sphere = 4/3 πr3


Radius of the cone = 3.5 = 7/2 cm


Height of the cone = 3 cm


Volume of the cone = 1/3 πr2h


Number of cones =






= 14×9 = 126 cones


So,


The number of cones formed is 126.


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