Table 1 Statistical Process Control (SPC) Problem Data *The Range and Row Average Help You Avoid Simple Math

Table 1 Statistical Process Control (SPC) Problem Data*
$\begin{array}{|c|c|c|c|c|c|}\hline \text { Sample } & \begin{array}{c}\text { Observation } \\\text { Number }\end{array} & \begin{array}{c}\text { Observation } \\\text { Number }\end{array} & \begin{array}{c}\text { Observation } \\\text { Number }\end{array} \\\hline \text { Number } & 1 & 2 & 3 & \begin{array}{c}\text { Row } \\\text { Average }\end{array} & \text { Row Range } \\\hline 1 & 10.1 & 10.6 & 9.6 & 10.1 & 1.00 \\\hline 2 & 9.7 & 9.4 & 9.0 & 9.37 & 0.70 \\\hline 3 & 10.1 & 9.1 & 10.3 & 9.83 & 1.20 \\\hline 4 & 10.1 & 10.3 & 10.9 & 10.43 & 0.80 \\\hline 5 & 10.2 & 9.8 & 9.0 & 9.67 & 1.20 \\\hline 6 & 10.6 & 10.2 & 9.5 & 10.10 & 1.10 \\\hline 7 & 9.5 & 10.2 & 10.2 & 9.97 & 0.70 \\\hline\end{array}$ *The range and row average help you avoid simple math errors and quicken the time to complete the SPC analysis but you have to know what to use when.
-Given the previous results and analysis for the R-chart, one would:

A) conclude that the R-chart is in statistical control and proceed to develop the x-bar chart.
B) conclude that the R-chart is not in statistical control and proceed to develop the x-bar chart.
C) investigate sample # 3 as it is outside the R-chart control limits and redo the R-chart.
D) plot the x-bar sample means first to see if they are randomly distributed.