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A manager wishes to build a 3-sigma range chart for a process. The sample size is six, the mean of sample means is 25.5, and the average range is 4.2. What are the UCL and LCL, respectively, for this range chart? Factors for Computing Control Chart Limits 3 sigma_.pdf 0.00 and 8.88 38.10 and 12.90 8.88 and 0.00 8.42 and 0 0 27.50 and 23.50
Mean Factor, Upper Range, Sample Size, n A2 D4 Lower Range, D3 0 2 2 WN 3 0 0 4 5 6 7 8 9 1.880 1.023 0.729 0.577 0.483 0.419 0.373 0.337 0.308 0.266 3.268 2.574 2.282 2.115 2.004 1.924 1.864 1.816 1.777 1.716 0 0 0.076 0.136 0.184 0.223 0.284 10 12