Q. X bar should never be interpreted when: (Solved)
1. R chart shows out of control points
2. X bar chart shows out of control points
3. The process mean is not known
4. None of the above
- a. R chart shows out of control points
1. R chart shows out of control points
2. X bar chart shows out of control points
3. The process mean is not known
4. None of the above