SOLUTION: If the surface area of a sphere is 64 Pi, what is its volume?

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Question 50603: If the surface area of a sphere is 64 Pi, what is its volume?
Answer by rapaljer(4671) About Me  (Show Source):
You can put this solution on YOUR website!
For a sphere

Volume: V=++%284%2F3%29%2Api%2Ar%5E3%29 and
Surface area: A=4%2Api%2A+r%5E2

64%2Api+=+4+%2Api%2A+r%5E2

Divide both sides by 4+pi:
+16+=+r%5E2 so r= 4.

Therefore, V=++%284%2F3%29%2Api%2Ar%5E3%29
V=++%284%2F3%29%2Api%2A4%5E3%29
+V+=%28256%2Api%29%2F3

R^2 at SCC