Question

The diameter of the moon is about 3500 km. Approximate the surface area of the moon using the formula for the surface area of a sphere, S = 4πr2. Write your answer in scientific notation.

Answer 1

`3.8465 *10^7` square kilometers

Explanation:

The surface area of a sphere can be found using the formula
`SA=4\pi r^2`. Since the diameter is 3500 km then its radius is half of this. 3500 divided in two is 1,750 units. Substitute r=1,750.

`SA=4\pi r^2\\SA = 4 \pi (1750)^2\\SA = 4 \pi *3,062,500\\SA =38,465,000`

The surface area of the moon is about 38,465,000 square kilometers. Write this is scientific notation using base.
`3.8465 *10^7`