Quadradic Equation Word Problems - Examples & Practice

Donnie's Donut Shop has hired you to make a big flat donut-shaped sign for his store. The donut has to have a hole with a diameter of $4$ feet and be even sided the whole way around. If Donnie gave you enough money to buy $37.7$ sq ft of sheet metal (about $12\pi$), how big should the radius, $r$, of the donut be?