SOLUTION: The formula for the volume of a sphere is V=4/3πr^3. Find the radius of a sphere with each volume. 1. 10 in^3 2. 20 ft^3 3. 0.45 cm^3 4. 0.002 mm^3 I tr

Algebra ->  Radicals -> SOLUTION: The formula for the volume of a sphere is V=4/3πr^3. Find the radius of a sphere with each volume. 1. 10 in^3 2. 20 ft^3 3. 0.45 cm^3 4. 0.002 mm^3 I tr      Log On


   

Question 586965: The formula for the volume of a sphere is V=4/3πr^3. Find the radius of a sphere with each volume.
1. 10 in^3
2. 20 ft^3
3. 0.45 cm^3
4. 0.002 mm^3
I tried doing the problems like this: 10/4/3π; it's not the right way, but I don't know how. It has to be answered as a radical expression. How do I do that?
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
The formula for the volume of a sphere is V=4/3πr^3. Find the radius of a sphere with each volume.
1. 10 in^3
Vol+=+4%2Api%2Ar%5E3%2F3+=+10
Solve for r
4%2Api%2Ar%5E3+=+30
r%5E3+=+30%2F%284%2Api%29+=+7.5%2Fpi
r+=+root%283%2C%287.5%2Fpi%29%29
r =~ 1.3365 inches
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You can do that for each one, or do it once and plug in the volumes.
You can make an Excel sheet to do them, too. Make it once, it works forever.
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Vol+=+4%2Api%2Ar%5E3%2F3
Solve for r
4%2Api%2Ar%5E3+=+3%2AVol
r%5E3+=+3%2AVol%2F%284%2Api%29
r+=+root%283%2C3%2AVol%2F%284%2Api%29%29 inches
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2. 20 ft^3
3. 0.45 cm^3
4. 0.002 mm^3
I tried doing the problems like this: 10/4/3π; it's not the right way, but I don't know how. It has to be answered as a radical expression. How do I do that?