TCO 3) Twenty samples of subgroup size 3 (n = 2) were collected for a variable measurement. Determine the upper control limit (UCL) for an R-chart if the mean of the sample ranges equals 6.4. Factors for calculating control limits n A2

TCO 3) Twenty samples of subgroup size 3 (n = 2) were collected for a variable measurement. Determine the upper control limit (UCL) for an R-chart if the mean of the sample ranges equals 6.4. 

 

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