## Thinking Mathematically (6th Edition)

The circular garden measures 10 yards across. This means that the diameter of the garden is 10 yards. The perimeter of a circle is its circumference. The circumference $C$ of a circle can be found using the formula $C=2\pi{r}$ where r = radius. The radius of a circle is one-half of the circle's diameter. Thus, the radius of the garden is: $r = \frac{1}{2}(10) = 5$ yards Solve for the circumference of the circle using the formula above to obtain: $C=2\pi(5) = 10\pi \approx 31.4159$ yards Therefore, there is a need for around 31 yards of fencing.