How do I calculate the percentage of errors, when I know min, max, mean, cp and CPK

#1 22nd March 2001, 05:00 AM

HI

I think I put it all in the subject line.

I have a problem for school. I asked a teacher a problem he couldn't answer, so now I have to find the solution.

I know the following:
CP
CPK
Minimum value
Maximum value
and the mean value.

I need to calculate how many % falls outside min min-max borders!

Can anyone help?

*Don Winton* · #2 22nd March 2001, 09:57 AM

What you need is located <a href="http://Elsmar.com/pdf_files/CPK.pdf" target=blank>here</a>. Specifically, pages 8 through 11. Standard PDF format, so you will need Acrobat Viewer to read it.

Hope this helps.

Regards,
dWizard

*Sam* · #3 22nd March 2001, 10:01 AM

For a normal distributation:

Zusl= USL - Xdbar/sigma.

Look up Zusl on a "standard normal distributation" table.

Do the same the Zlsl

#4 2nd April 2001, 05:02 AM

Thank you very much for your help.

The Juran Trilogy	The Deming PDCA Cycle	QMS Implementation	FMEA Information	APQP Information
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Identifying Waste	Pull Systems	Lead Time Reduction	Planned Maintenance	Quick Setup
Discovering Change	Process Capability - Cp vs. Cpk	Histogram Animation	Process Loop Animation	Taguchi Loss Function
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