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Real world problem?

Ok, I've inherited a quality control responsibility, and the former QC person is long gone, so I don't have any resource on how to determine the numbers. We manufacture widgets. In the course of a day, we make 10,000 widgets. Of the daily production, we pull 1,000 and inspect them. Of the 1,000 pulled, 351 are determined to have flaws. Of the 351 flawed widgets, it's determined that 75 of them are flawed enough to be unsalable. We use a quality ratio....1 flaw in XX widgets. I've been determining the quality ratio like this: 1000 widgets that were inspected, there were 352 flaws. Of the 352 flaws, 75 were critical (unsalable). The quality ratio is 13.3 to 1. (1000/75) Is this correct, or am I just basically pulling numbers outta my butt? The company standard is 1 flaw in 85 widgets, and it affects people's bonuses...so I'm REALLY interested in getting the quality ratio correct. Correction: Company standard is 1 CRITICAL flaw in 85 widgets. Heather: Managers here can't deal with numbers involving decimal points.....that's why we use the "1 error in <number> widgets" instead of a percentage. :)

Public Comments

1. I think you have the ratio backwards... You have 75 flaws in every 1000, so it should be 75/1000 = 0.075
2. Let the units on the quantities help you. 1 flaw in 85 widgets can be written as the ratio: 1/85 (flaws/widget) So, if you have 75 flaws in 1000 widgets, you have 75/1000 (flaws/widget) 1/85 = 0.0177 75/1000 = 0.075 It looks like you are exceeding standards by quite a bit.