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.

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.

The circumference of a circle is its outside edge, and is the same distance from the centre at every point along its length. This distance is called the radius.

After you make it all the way around, the program calculates the circumference and radius of your circle—and from that, the value of pi. You can see the code by clicking the pencil icon.

Going further, if you used 40 digits of pi, Rayman says, you could calculate the circumference of the entire visible universe — an area with the radius of about 46 billion light-years — “to ...