I made a mistake! The sample standard deviation is 0.026, not 0.0026
I have been looking around, and can’t find the piece of paper that had my notes on when I made the video. There are two possibilities.
1. I did the math wrong, and didn’t divide before taking the square root
2. I did the math right, but mis-read the decimal place on my piece of paper
I hope it was #2, but #1 is also possible. I will re-record the video, but not today
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We compute the control limits for a P chart
p-bar = average defect rate = total number of defective items, divided by the total number of items sampled
n-bar = average sample size
s = sample standard deviation
UCL = p-bar + 3 * s
LCL = p-bar - 3 * s
