Twenty samples of subgroup size 3 (n=3) were collected for a variable measurement. Determine the upper control limit (UCL) and lower control limit (LCL) for an R-chart if the mean of the sample ranges equals 4.4.
- UCL = 9.3016, LCL = 0.3344
- UCL = 1.4696, LCL = 0.0000
- UCL = 11.3256, LCL = 0.0000
- UCL = 8.8176, LCL = 0.0000