From the R chart, it can be observed that the R chart uses the sample which ranges to examine the alteration in the spread of a process in controlling the weight of a box of cereal. The sample ranges are plotted as points on the chart and is connected with lines. Moreover, the solid line in the center is the mean of the sample ranges.
Besides it, from the chart, it can be observed that the two dashed lines reflect the lower control limit that is ...