Question

PLEASE HELP!!!!!

A sphere has a circumference of its great circle equal to 20 Pi what is the volume of that sphere?

Answer 1

Explanation:

The formula for the volume of a sphere is

`V=(4)/(3)\pi r^3` In order to use this formula we have to have a value for the radius and right now we don't. But we can find it indirectly by using the circumference formula. The circumference formula is

`C=2\pi r` If the circumference is 20π, then we will fill that in for "C" and solve for r:

20π = 2πr and if you divide both sides by 2π, you'll get that r = 10. Now we have a radius.

Using that in the volume formula:

`V=(4)/(3)\pi (10)^3` and then simplifying a bit:

`V=(4)/(3)\pi (1000)` and

`V=(4000\pi)/(3)` which divides to give you

`V=1333.33\pi`, third choice down.