Statistics
posted by Johnny .
Construct the appropriate control chart for the observations listed below, using 3 sigma limits.
Product Number  Number of defects
1  3
2  3
3  6
4  5
5  3
6  5
7  2
8  2
9  3
10  4
11  6
a. Determine the upper and lower control limits.
b. Discuss the chart you have plotted. What conclusions and recommendations do you make from the chart and the data?

Here's what you will need to answer this question:
Lower limits = mean  3(sd/√n)
Upper limits = mean + 3(sd/√n)
sd = standard deviation
n = sample size
You will need to calculate the mean and standard deviation from the data given. Once you have those values, you can then determine the lower and upper limits.
I hope this will help get you started.
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