The CircleThe RADIUS R is the distance from the center to the edge. The DIAMETER D is the distance across the circle. The CIRCUMFERENCE C is the distance around the edge of the circle. It's the perimeter of the circle. The diameter D is twice the radius R or
The circumference C is ("pi") times the diameter D
is 3.1415926...(goes on forever), but just use 3.14 for The area A of a circle is:
So, for a circle whose radius R is 6 inches:
