A process $($Process #$262)$ is under study to be controlled using control Ilimits and $x$ and $R$ charts.

Samples from process to be controlled

Using the above table of samples the prellminary $UC{L}_R$ is calculated as $.$ The prellminary $LC{L}_R$ is calculated as $0.$

After discarding any points that fall outside the control IImits the final $UC{L}_R$ Is calculated as $,$ the final $LC{L}_R$ is calculated as $0,$ and the $R$ control chart mean is calculated as

We now need to calculate the $\stackrel{}{x}$ charts control limits$.$ The prellminary UCL $\stackrel{}{x}$ Is calculated as $$ and the prellminary $LCL\stackrel{}{x}$ Is calculated as

After discarding any outtying samples, and repeating until no samples are outside the limits$,$ the final mean is $,$ with a final $UC{L}_{\stackrel{}{x}}$ of $$ and a final $LCL\stackrel{}{x}$ of