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 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.

This article was originally published with the title “The Circumference of a Circle of Given Radius” in SA Supplements Vol. 72 No. 1860supp (August 1911), p. 135 doi:10.1038 ...