A sample of 50 customers from a large normal population has a mean waiting time of 23 minutes. We know from past testing that the population standard deviation is 4 minutes. Determine a 95% confidence interval for the true mean (waiting time) of the population. What is the lower boundary for the CI?
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A sample of 50 customers from a large normal population has a mean waiting time of 23 minutes. We know from past testing that the population standard deviation is 4 minutes. Determine a 95% confidence interval for the true mean (waiting time) of the population. Group of answer choices (21.8913, 24.1087)
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