The circumference formula for a circle is 2PiR, or 2 x Pi (3.14) x the radius, or PiD (Pi x Diameter). Multiply 3.14 by 3.2 for our circumference. 3.14 x 3.2 = 10.048. Your Circumference is 10.048 (if not rounded). If rounded, 10.05. I hope this helps!