# What is the size of the Earth's surface?

Dec 21, 2015

Use the formula for the surface area of a sphere to get an approximate value of $200 , 000 , 000 = 2 \times {10}^{8}$ 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:

$4 \pi {4000}^{2} \approx 200$ million square miles