SOLUTION: The volume of a sphere is numerically equal to the surface area of the sphere. If this value is equal to Nπ, what is the value of N?

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Question 721154: The volume of a sphere is numerically equal to the surface area of the sphere. If this value is equal to Nπ, what is the value of N?
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
vol of sphere = 4/3 pir^3
surface area = 4 pir^2
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4/3 pi r^3= N pi
N= 4/3 r^3
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N pi = 4 pi r^2
N= 4r^2
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equate both
4r^2=4/3 r^3
r=3
N= 4r^2
N= 4*3*3
N=36