A solid sphere of radius 3cm is melted and then cast into small spherical balls each of diameter 0.6cm. Find the number of balls thus obtained.

Explanation

when a shape is melted and recast into another shape then volume of both shapes will remain same.

Let number of small balls be `x`

Radius of sphere, `r=3cm`

Radius of smaller spherical balls, `R=0.6/2=0.3cm`

Therefore, Volume of x small balls = Volume of sphere

`4/3piR^3xx(x)=4/3pir^3`

`x=r^3/R^3`=3^3/0.3^3`

`x=1000`

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