How do you find the circumference of a circle when you know the area?

So if i have a circle with an area of 100 meters squared how do you find the circumference?

You need to work backwards.

You know that the area of a circle is found using the formula A = pi (3.14) x radius x radius. So, if you divide the known area (100 meters) by pi (3.14), you will get the radius squared.

Then you need to find the square root of that to have the actual length of the radius which you know is half of your diameter.

Finally, just use the diameter to determine the circumference of the circle. The formula for that is C = pi x diameter.

Now that you know how to do it, you can find the answers for yourself.

This entry was posted on Friday, June 25th, 2010 at 1:31 pm and is filed under circle area. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.

One Response to “How do you find the circumference of a circle when you know the area?”

OneQuietVoice on June 25th, 2010 at 7:07 pm

You need to work backwards.

You know that the area of a circle is found using the formula A = pi (3.14) x radius x radius. So, if you divide the known area (100 meters) by pi (3.14), you will get the radius squared.

Then you need to find the square root of that to have the actual length of the radius which you know is half of your diameter.

Finally, just use the diameter to determine the circumference of the circle. The formula for that is C = pi x diameter.

Now that you know how to do it, you can find the answers for yourself.
References :

Area List