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Question
How many lead balls, each of radius 1 cm, can be made from a sphere of radius 8 cm?
Solution
Radius of the sphere = R = 8 cm
Volume of the sphere =`4/3 piR^3 = 4/3pixx8xx8xx8 =4/3pi xx 512 "cm"^3`
Radius of each new ball = r =1 cm
Volume of each ball `=4/3 pir^3 = 4/3pixx 1xx1xx1 = 4/3pixx1 "cm"^3`
Total number of new balls that can be made`= "Volume of sphere "/"Volume of each ball" = (4/3pixx512)/(4/3pixx1) = 512`
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