# If the radius of a circle is 5.5cm what is the diameter?

The diameter of any circle is twice the radius.

### If the radius of a circle is 10 inches what is the diameter?

The radius is half the diameter. The diameter is twice the radius. If the radius is 10 inches, the diameter is twice that, or 20 inches. The radius is any straight line that connects a point on the circle with it's center. The diameter is a line segment that connects two points on a cirle throught the center of the circle. Answer: Let r be the radius of the circle and d be the diameter…