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Find Out Things About Circles

This page will show you how to calculate various things that pertain to a circle.

Notes about circles:

  • The radius R, or the distance from the center of a circle to its edge, is usually the defining property of a circle.

  • The diameter, or the distance across a circle that passes through the center of the circle is 2R (twice the radius).

  • The circumference, or distance around a circle is 2R.

  • The area enclosed by a circle is R2

  • Note that =3.1415926535...

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