1. (TCO 12) Six samples of subgroup size 2 (n = 2) were collected.

1. (TCO 12) 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 (Points : 10)