How do you find the area of a circle? Can you measure the area of a circle and use that to find a value for Pi?

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.

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 ...

You draw a circle. From that circle, you can determine both the circumference and the radius. Then the value of pi would be the circumference divided by twice the radius. Simple, right?

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.

The mathematical constant, which is the ratio of a circle’s circumference to its diameter, can be used to find the area or circumference of a circle -- or of that pie you’re hopefully enjoying ...