Question

A small beach ball has a radius of 8 inches. A larger beach ball has a volume that is twice the volume of the small ball. What is the best approximation for the radius of the large beach ball?

Answer 1

Hello Mikaelab!
Let x = the radius of the large ball.
\[\frac{ 4 }{ 3 }\times \pi r^2=2(\frac{ 4 }{ 3 }\times \pi 8^3)\]
Multiply both sides by 3 to get, to get rid of the denominator, Find 8^3
\[4(\pi \times r ^3) = 8(\pi \times 512)\]
Divide both sides by \[4 \times \pi\]
\[r^3=2(512)\]
\[r^3=1024\]
\[r = 3\sqrt{1024}\]
r = 10.08 inches, radius of the larger.