This document discusses formulas for circumference and arc length. It states that circumference C equals 2πr or πd, where r is the radius and d is the diameter. It also explains that arc length is calculated as a percentage of the circumference by taking the arc measure in degrees and dividing by 360, then multiplying that fraction by the circumference.

1. Terms of Endearment
Circumference and Arc
Length: 11.4

2. Circumference
• C=2(pi)r or C=(pi)d

3. Arc Length
• Arc length is really a percentage of
the circumference, so we take that
percentage of the circumference by
taking the arc’s degrees and dividing
by 360 to find out what part we are
measuring
• (Arc Measure/360)(circumference)