You are managing a customer service center. One of the key aspects of managing this department is the average time on hold for your customers. You have decided to randomly sample 7 customer calls each hour and measure the time on hold. You would like to know if something different happens in your organization so you can address any issues that arise. You have decided to use statistical process control to identify when special causes of variation are present. Use that data to calculate the upper and lower control limits for your x-bar and r-charts. You do not know the population standard deviation. Enter your calculations and answers in the green cells. (The chart from the book is at the bottom of this sheet) After calculating the control limits for your chart, you restart your sampling and find the following data. 5) Does the X-bar Chart show that the process is in statistical process control? 6) Does the R-Chart show that the process is in statistical process control? 7) Overall, is the process in statistical process control? \begin{tabular}{|l|r|r|r|r|} \hline 43 & Control Limit Factor Table for X-Bar \& R-Charts \\ \hline 44 & & & & \\ \hline & \# & X-Chart & R-Chart & R-Chart \\ \hline & Observation & Factors for & Factors for & Factors for \\ \hline & sin Sample & Control & Control & Control \\ \hline 45 & (n) & Limits (A2) & Limits (D3) & Limits (D4) \\ \hline 46 & 2 & 1.88 & 0 & 3.27 \\ \hline 47 & 3 & 1.02 & 0 & 2.57 \\ \hline 48 & 4 & 0.73 & 0 & 2.28 \\ \hline 49 & 5 & 0.58 & 0 & 2.11 \\ \hline 50 & 6 & 0.48 & 0 & 2 \\ \hline 51 & 7 & 0.42 & 0.08 & 1.92 \\ \hline 52 & 8 & 0.37 & 0.14 & 1.86 \\ \hline 53 & 9 & 0.34 & 0.18 & 1.82 \\ \hline 54 & 10 & 0.31 & 0.22 & 1.78 \\ \hline 55 & 11 & 0.29 & 0.26 & 1.74 \\ \hline 56 & 12 & 0.27 & 0.28 & 1.72 \\ \hline 57 & 13 & 0.25 & 0.31 & 1.69 \\ \hline 58 & 14 & 0.24 & 0.33 & 1.67 \\ \hline \end{tabular} \begin{tabular}{|c|r|r|r|r|} \hline & 7 & 0.42 & 0.08 & 1.92 \\ \hline & 8 & 0.37 & 0.14 & 1.86 \\ \hline & 9 & 0.34 & 0.18 & 1.82 \\ \hline & 10 & 0.31 & 0.22 & 1.78 \\ \hline 6 & 11 & 0.29 & 0.26 & 1.74 \\ \hline 6 & 12 & 0.27 & 0.28 & 1.72 \\ \hline 5 & 13 & 0.25 & 0.31 & 1.69 \\ \hline 59 & 14 & 0.24 & 0.33 & 1.67 \\ \hline 60 & 15 & 0.22 & 0.35 & 1.65 \\ \hline 61 & 16 & 0.21 & 0.36 & 1.64 \\ \hline 62 & 17 & 0.2 & 0.38 & 1.62 \\ \hline 63 & 18 & 0.19 & 0.39 & 1.61 \\ \hline 64 & 19 & 0.19 & 0.4 & 1.6 \\ \hline \end{tabular}