SOLUTION: The volume of a sphere is numerically equal to twice its surface area. What is the radius of the sphere?

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Question 1027010: The volume of a sphere is numerically equal to twice its surface area. What is the radius of the sphere?
Found 2 solutions by Alan3354, Fombitz:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
The volume of a sphere is numerically equal to twice its surface area. What is the radius of the sphere?
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4pi%2Ar%5E3%2F3+=+4pi%2Ar%5E2
Solve for r.

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
For a sphere,
V=%284%2F3%29pi%2AR%5E3
SA=4pi%2AR%5E2
So,
%284%2F3%29pi%2AR%5E3=4pi%2AR%5E2
R=3