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Question
How many balls each of radius 1 cm can be made by melting a bigger ball whose diameter is 8 cm?
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Solution
Diameter of bigger ball = 8 cm
Therefore, Radius of bigger ball = 4 cm
Volume = `4/3pir^3`
= `4/3pi xx 4 xx 4 xx 4`
= `(256pi)/3cm^3`
Number of balls = `(( 256pi)/3)/((4pi)/3)`
= `(256pi)/3 xx 3/(4pi)`
= 64
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