You are developing an X-bar chart based on sample means. You know the average range is 4, the sample size is 15, and the average of the sample means is 20. Which of the following is your LCL? exhibit 13.7 O 19.12 Number of Observations each sample O 20.88 2 3 12 16 Link to the pdf version of the table or for Determining from R the Three-Sigma Control Limits X- and R-Charts Q Search X-Chart A 1.88 1.02 0.73 0.58 0.48 0.42 0.37 0.34 0.31 0.29 0.27 0.25 0.24 0.22 0.1 Factors for R-Chart Lower Control Limit D 0 0 0 0 0.08 0.14 0.18 0.22 0.26 0.28 0.31 0.33 0.35 0.36 0.38 Upper Control Limit D 3.27 2.57 2.28 2.11 2.00 1.92 1.86 1.82 1.78 1.74 1.72 1.69 1.67 1.65 1.64 1.62 Employee 18

You are developing an X-bar chart based on sample means. You know the average range is 4 , the sample size is 15 , and the average of the sample means is 20 . Which of the following is your LCL