Question

The distance around the middle of a sphere (the circumference) equals 37.699 in. what is the surface area of the sphere?

Answer 1

To solve this problem you must apply the proccedure shown below:

1. Clear the radius from the formula for the circumference of a circle and substitute values, as following:

$C=2\pi r\\ r=C/2\pi \\ r=37.699in/2\pi \\ r=5.99in$

2. Substitute the radius calculated into the formula for calculate the surface area of the sphere:

$SA=4\pi r^{2} \\ SA=4\pi(5.99in^{2})\\ SA=450.88in^{2}$

The answer is: $450.88in^{2}$