This applet takes samples of size 31 from a normal distribution with population mean 80 and standard deviation 2. Click on the "One Sample" button to see the sample and the computations for the 95% confidence interval. The confidence interval is represented in blue if the interval includes the true population mean of 80 and red if it does not. Then click on the "10 Samples" and then "100 Samples" button to see the results for multiple samples. About 95% of the confidence intervals should include the true population mean of 80.
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