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# The surface area of a sphere is A pi cm^2 and the volume of the sphere is B pi cm^3

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The surface area of a sphere is A pi cm^2 and the volume of the sphere is B pi cm^3 where both A and B are three-digit whole numbers. Find the radius of the sphere.

Oct 29, 2020

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Surface area of a sphere  $= 4 \pi r$

Volume = $\frac{4}{3} \pi r$

Because they are three digits and whole, we know that r is divisible by 3. In other words, $r=3n$ where n is all integers.

Looking at the three digit part, we have $r = 300x+30y+3z,$ where x, y, and z are integer digits 0-9.

It is impossible to determine a unique value for r and thus the question needs more information.

Oct 29, 2020
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Your formulas are not correct Pangolin Melody  Oct 29, 2020
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The surface area of a sphere is A pi cm^2 and the volume of the sphere is B pi cm^3 where both A and B are three-digit whole numbers. Find the radius of the sphere.

I get  r=6  or  r=9

If r= 6  then A=144  and B=288

If r=9  then   A=329     and     B=989

Oct 29, 2020