A circle is 360° all the way around; therefore, if you divide an arc's<span> degree </span>measure<span> by 360°, you </span>find<span> the fraction of the circle's circumference that the </span>arc<span> makes up. Then, if you multiply the length all the way around the circle (the circle's circumference) by that fraction, you </span>get<span> the length along the </span>arc<span>.</span>