A city newspaper has stated that the average time required to sell a used car advertised in the paper is less than 5 days. Assuming that the population standard deviation is 2.1 days, if the "true" population mean is 4.1 days and a sample size of n = 49 is used with an alpha equal to 0.05, the probability that the hypothesis test will lead to a Type II error is approximately .0869.

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Given the population standard deviation (σ) is 2.1 days, the true population mean (μ) is 4.1 days, and the sample size (n) is 49, with an alpha (α) of 0.05, the calculation for the probability of a Type II error (β) under these conditions indeed results in approximately 0.0869. This calculation involves determining the z-score for the sample mean under the null hypothesis and then finding the corresponding probability that the test fails to reject the null hypothesis when the alternative hypothesis is true.

A City Newspaper Has Stated That the Average Time Required