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8. Sampling Distributions & Confidence Intervals: Proportion
8. Sampling Distributions & Confidence Intervals: Proportion / Confidence Intervals for Population Proportion / Problem 6
Problem 6

The durability times (in hours) of 1212 randomly selected ceiling fans have a sample standard deviation of 0.40.4 hours. Assume the data come from a normally distributed population. Using an 80%80\% confidence level, construct the confidence interval for the population variance (σ2\sigma^2). Also, interpret the results.