# Circumference

### Concept (1)

Circumference can be thought of as the "perimeter" of a circle or the distance around a circle. Since pi is the ratio of circumference to diameter, circumference can be calculated by multiplying the circle's diameter by pi. Another formula substitutes d = 2r, where one diameter equals two radii, and C = 2(r)(pi). Related topics include area of a circle, arc length, and parts of a circle.

### Sample Problems (4)

Problem 1

How to calculate the circumference of a circle given diameter or radius.

Problem 2

How to find the radius of a circle given circumference.

Problem 3

How to find the perimeter of a figure that appears to be a track.

Problem 4

How to find the circumference of a figure formed by two different circles and a straight line.
{"found_math": false, "script_math_tex": 0, "script_math_asciimath": 0, "math_annotations": 0, "math_alttext": 0, "mathml": 0, "mathjax_tag": 0, "mathjax_inline_tex": 0, "mathjax_display_tex": 0, "mathjax_asciimath": 0, "img_math": 0, "codecogs_latex": 0, "wp_latex": 0, "mimetex.cgi": 0, "/images/math/codecogs": 0, "mathtex.cgi": 0, "katex": 0, "math-container": 0, "wp-katex-eq": 0, "align": 0, "equation": 0, "x-ck12": 0, "texerror": 0}