QC Study Problems

Here are some solved problems in the text that relate to the quality control techniques that we've presented in class. As mentioned, the best way to learn these is to actually DO the work (i.e., put pencil to paper)--don't merely review the problem in the text. It will pay off come exam time (believe me, I'm speaking from experience!).

Technique	Text Location
X-bar chart	Explained example of "silicon wafer production" beginning on p. 695 of text; I would also work thru the LaVentana case data; you can also work thru the Dean Door case data here.
c-chart	Explained example of "machine failures" beginning on p. 730 of text; I would also work thru the Disciplinary Citation case data (answers can be found here on the c-chart sheet tab).
p-chart	Explained example of "zip code reader" beginning on p. 722 of text (answers can be found here on the p-chart sheet tab); I would also work thru the Murphy Trucking case data.
Process capability index (Cp)	Explained example of process capability index using "silicon wafer production" data beginning on p. 710 of text; Prob #16 p. 754 (answer in back--look for Cp only. Note that book says Cp of 1.098 is "adequate" which I'd dispute. Recall our rule that we want Cp > 1.3); a process capability example using the Dean Door data can be found here under the process capability tab.

Site maintained 1999-2013 by Matthew W. Ford.