## Elementary Geometry for College Students (6th Edition)

A circular lock washer whose outside circumference measures 5.48 cm is used in an electric box to hold an electrical cable in place To find the outside radius to the nearest tenth of a centimeter. We know the circumference of the circle is given by the formula c= $\pi$ d = 2$\pi$ r 5.48 = 2 * 3.14 * r r = $\frac{5.48 }{2 * 3.14}$ = 0.872 cm