Question

The radius of the Earth is approximately 3,960 miles. Find the approximate surface-area-to-volume ratio of the Earth.

Answer 1

There are two things you need to know here
\[A=4\pi r^2 \]
\[V=\frac{ 4 }{ 3 }\pi r^3\]

Answer 2

Calculate both with r=3960 and take the ratio

Answer 3

If you are clever you can save a lot of calculation for yourself by simplifying first :)