The first case study is now posted under Week 6. Read it very carefully. There are several parts to it. Along with the white boards it contains all the information you should need to answer it well, although Chapter 20 of the textbook is very helpful as well. It is an Excel file and you can use Excel’s capabilities to make calculations easier, although it is important that I can see your logic and approach as well. Hand drawn control charts are fine, and ensure the key values asked for are written. I will give partial credit even if there are math errors provided that the approach is good. Note that there is more than one way to calculate Cp and Cpk and they may give slightly different numbers – either method is OK but show your working clearly.
Excel allows you to calculate arithmetic means (often called averages), ranges, and standard deviations very easily, and the case study is already in Excel.