Control charts for X bar and R are kept on the weight in kilograms of a color pigment for a batch process. After $25$ subgroups with a subgroup size of $4,$

summation of x bar $=52\mathrm{.}08$ kg $(114\mathrm{.}8$ Ib$)$

summation of R $=11\mathrm{.}82$ kg $(26\mathrm{.}1$ Ib$).$

Assuming the process is in a state of control, compute X bar and R chart central line and control limits for the next production period.

You can use this blank Excel file