To Create a Best Fit Circle
By using the Best Fit option, you can create a Constructed Circle through several points. You must select at least three points (or entities that represent points). If you select more than three points, the system constructs the circle that provides the best fit for all the selected points.
1. Click > 
Circle. The CMM Construct tab opens.
Circle. The CMM Construct tab opens.2. Select the parent reference Csys from the Parent Csys drop-down list.
3. Select Best Fit from the Type drop-down list.
4. Select 3 or more measure or construct steps of the following types:
◦ Point
◦ Circle (center)
◦ Cone (cone vertex)
◦ Sphere (center)
5. Click OK.