For an xbar and R control chart use the following summary st

For an xbar and R control chart use the following summary statistics: = 10.0, =2.3, and n=4 to answer the following questions.

Calculate the upper control limit for an R control chart.

5.249

9.146

14.234

9.26

Solution

Upper control limit for an R-chart = R-bar * D₄

For n = 4,

D₄ = 2.282

Thus,

UCL = 2.282 * 2.3

= 5.249.

Hope this helps.