SOLUTION: If a hemisphere has the same volume as a cylinder how can you work out the hemisphere's radius

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Question 880847: If a hemisphere has the same volume as a cylinder how can you work out the hemisphere's radius
Found 2 solutions by Fombitz, ewatrrr:
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
The volume of a sphere is,
V%5Bs%5D=%284%2F3%29pi%2AR%5Bs%5D%5E3
So the volume of a hemisphere is half that,
V%5Bhs%5D=%282%2F3%29pi%2AR%5Bs%5D%5E3
The volume of the cylinder is,
V%5Bc%5D=pi%2AR%5Bc%5D%5E2%2AL
If you know the volume of the cylinder then,
V%5Bc%5D=%282%2F3%29pi%2AR%5Bs%5D%5E3
R%5Bhs%5D%5E3=%283V%5Bc%5D%29%2F%282pi%29
R%5Bhs%5D=%28%283V%5Bc%5D%29%2F%282pi%29%29%5E%281%2F3%29

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
Vhemisphere= 4/6pir^3
Vcylinder = pir^2h
+%284%2F6%29pi%2Ar%5Bhs%5D%5E3=+pi%2Ar%5Bc%5D%5E2h
sqrt%28%284%2F6%29r%5Bhs%5D%5E3%2Fh%29+=+r%5Bc%5D