A cylindrical rod of iron, whose height is equal to its radius, is melted and cast intospherical balls whose radius is half the radius of the rod. Find the number of balls.

A cylindrical rod of iron, whose height is equal to its radius, is melted and cast intospherical balls whose radius is half the radius of the rod. Find the number of balls. Correct Answer 6

Volume of rod = πr2h = πr2×r = πr3  

Volume of one spherical ball =r/2 

Volume of the spherical ball = 43πr38  

Number of balls=Volumeof rod/volumeof one ball

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