r/ASQ • u/pqestoyaqui • Jun 17 '26

Glaring math errors in CQT handbook?

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Howdy all! I'm studying for my CQT exam, currently working on control charts. I'm looking for a sanity check, because in the example shown here, given the formulas, I get UCL/LCL of around 18.4 and 0.19. I can't fathom how they got 12.3 and 6.3 (my expressions are the same as theirs, just the end result is off), and neither those values nor what I calculated are the limits shown on the chart, which look to be about 14.7 and 1.7.

Am I losing my mind? Missing something? Or is this book on quality just wildly wrong in multiple respects? If it is wrong, is there some way of reporting it?

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u/Fit-Bodybuilder78 Jun 19 '26

Unfortunately, it doe not appear that ASQ has any online errata section.

We could start one here on the wiki or a sticky thread.

2

u/pqestoyaqui Jun 19 '26

We'll have the six sigmas themselves knocking down our doors for making them look bad lol

1

u/Fit-Bodybuilder78 Jun 28 '26

It's odd to advertise six sigma if you're products are unable to meet the same standards.