Question

What is the size of the Earth's surface?

Answer 1

Use the formula for the surface area of a sphere to get an approximate value of `200,000,000 = 2xx10^8` square miles

Explanation:

The surface area of a sphere of radius `r` is `4 pi r^2`

The radius of the Earth is approximately `4000` miles

So the surface area of the Earth is approximately:

`4 pi 4000^2 ~~ 200` million square miles