Ok, to find the feet of fencing material that she need we need to calculate the perimeter of the circle.
We are going to use the folling formula:
[tex]\text{Perimeter}=2\pi r[/tex]So, replacing:
[tex]\text{Perimeter}=2(\frac{22}{7})\cdot7[/tex][tex]=\frac{44}{7}\cdot7=44[/tex]She need 44 feet of fencing material.
