Find the diameter and the radius of a circle with a circumference of 465 cm. Give the answer to the nearest centimetre. Use π = 3۰142 or the π button on a calculator.

I am Pi, the ratio of the circumference of a circle to its diameter. Picking up the phone here at the Smithsonian, I set out to find out more about Pi and how it is represented in the national ...

What Is a Circle? My favorite way to define a circle is in terms of how to draw one. In the episode What Is Pi? we learned how to draw a circle arts-and-crafts style. To do this, start by cutting ...

How to Solve for Radius in Excel. The radius of a circle or a sphere is the distance between the center and the edge. The radius can be used to calculate a circle's diameter, area and circumference.

Learn about the definition of pi in relation to a circle with this BBC Bitesize Maths article. For students between the ages of 11 and 14.