To find<span> the perimeter of the </span>quarter circle<span>, </span>find<span> the circumference of the whole </span>circle<span>, divide by 4, and then add the radius twice. To </span>find<span> the radius when you are given the </span>area<span> of the </span>quarter circle<span>, multiply the given </span>area<span> by 4, then plug this number in for A into the formula A = pi * r^2 and then solve for r.</span>
