The circumference of a circle is given by:
[tex]C = 2 \pi r[/tex]
We can solve for r:
[tex]r = \frac{C}{2 \pi } [/tex]
Plug in given values:
[tex]r = \frac{75.4}{2 \pi } [/tex]
Plug it into a calculator to get:
[tex]r = 12[/tex]
So, your answer is: r = 12cm.