Question

1. The manager of an assembly line took five samples each with six observations, under ideal conditions to develop control limits for an X-bar chart and R-chart. The mean and the range for each sample is shown in the table below.

   Sample Number         Sample Mean       Sample Range

            1                          2.18                          0.33

            2                          2.12                    0.38

            3                          1.88                    0.44

            4                          1.99                    0.38

            5                          2.02                    0.32

1. Calculate the UCL and LCL for the X-bar Chart and the R-chart. (Use the chart on appendix B for the value of A2, page 398 in the book).
2. Construct the X-bar chart and the R-chart. Please watch the example video for this chapter to construct these charts. I prefer to see the charts being drawn manually, by hand, instead of MS Excel because most students who used excel ended up submitting charts that didn’t look like control charts .
3. What can you conclude about the assembly line process base on the two charts?

Answer 1