Six samples of subgroup size 2 (n = 2) were collected. Determine the upper control limit (UCL) for an X-bar chart if the mean of the sample averages is 4.7 and mean of the sample ranges is 0.35.
Factors for calculating control limits
n A2 D3 D4
2 1.880 0 3.267
3 1.023 0 2.574
4 0.729 0 2.282
5 0.577 0 2.114
6 0.483 0 2.004