Consider the large hospital that wants to estimate the average length of stay of its patients, μ. The hospital randomly samples n = 100 of its patients and finds that the sample mean length of stay is = 4.5 days. Also, suppose it is known that the standard deviation of the length of stay for all hospital patients is σ = 4 days. Use the interval estimator ± 1.96 σ to calculate a confidence interval for the target parameter, μ.
