Circumference Of A Circle Formula: A circle consists of all points in a plane that are a given distance, called the radius, from a given point called the center.
A segment or line can intersect a circle in several ways.
• A segment with endpoints that are the center of the circle and a point of the circle is a radius.
• A segment with endpoints that lie on the circle is a chord.
• A chord that contains the circle’s center is a diameter.
The circumference of a circle is the distance around the circle.
For a circumference of C units and a diameter of d units or a radius of r units,
C = π.d or C = 2πr
Example: Find the circumference of the circle to the nearest hundredth.
Answer: C = 2πr ⇒ Circumference formula
⇒ 2π(13)
≈ 81.68 (Use a calculator)
The circumference is about 81.68 centimeters.