You know the circumference. You want to find the radius.
This is using the reverse circumference formula!
CIRCUMFERENCE OF A CIRCLE:
[tex]2 \pi r[/tex] = circumference
Now plug in. [tex]2 \pi r = 72 \pi [/tex]
Simplify and isolate r.
[tex]2r=72[/tex]
[tex]r=36[/tex]
the radius is 36.
