| Sample number |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
Total |
| Mean (\(\overline {X}\)) |
15 |
17 |
15 |
18 |
17 |
14 |
18 |
15 |
17 |
16 |
\(\sum\)\(\overline {X}\) = 162 |
| Range (R) |
7 |
7 |
4 |
9 |
8 |
7 |
12 |
4 |
11 |
5 |
\(\sum\)R = 74 |
The above diagram shows all the three control lines with the data points plotted. We see that all the points of the sample mean are within the control limits. We now draw the R chart for the given data.
The above diagram shows all the three control lines with the sample range points plotted. We observe that all the points are within the control limits.
Conclusion: From the above two plots of the sample mean \(\overline {X}\) and sample range R, we conclude that the process is in control.
