Use the formula: arc length = rθ
Use the formula: arc length = (θ/360) × 2πr
Let r be the radius
Let θ be the central angle in radians for rθ
Let θ be the central angle in degrees for (θ/360) × 2πr
Convert degrees to radians if needed: radians = degrees × π/180
Substitute the radius and angle into the appropriate formula
Calculate the result using the same units as the radius