So,
The formula for the circumference of a circle:
[tex]C = 2 \pi r\ or\ C = \pi D (diameter)[/tex]
We can now substitute the given values and solve for D.
[tex]12 \pi = \pi D[/tex]
Divide both sides by pi.
[tex]12 = D[/tex]
The diameter of the circle is 12 units.
