Question

A lumber company makes plywood for residential and commercial construction. Every hour, five pieces of plywood are selected and the thicknesses are measured. The accompanying graphs are the control charts for the first 20 subgroups. Suppose this process remained in control for the next 40 hours. The accompanying data are the thickness measurements for hours 41 through 43. Based on these data and the two control charts, what should be concluded about the process? Has the process gone out of control? Click the icon to view the plywood thickness data. Click the icon to view the control charts for the first 20 subgroups. Plywood Thicknesses Х Determine the subgroup means and ranges for hours 41 through 43. Hour Mean Range 0 41 Hour Panel 1 Panel 2 Panel 3 Panel 4 Panel 5 42 41 0.763 0.735 0.722 0.719 0.751 43 42 0.776 0.792 0.798 0.769 0.813 0.787 0.773 (Type integer or decimals.) 43 0.768 0.799 0.824 Print Done

Answer 1

Hour plean =0.738 42 00763+0 1735+0.722+0.789 +0.751] / 5 [0.769+0.787+0.776+0.792 +0.798]/5 = 0.784 [0.813 4 0.773+0.768+0.799+0.824)/5 = 43 0.795 Hour 1 Range 0.763-0.49=0.044 42 0.79.8 -0.769= 0.029 43 0.824-0.768 = 0.056 And Hour Mean Range 41 0.738 0.044 42 0.784 0,029 43 0795 10.056