A sporting goods store believes the average age of its customers is 39 or less. A random sample of 46 customers was surveyed, and the average customer age was found to be 42.5 years. Assume the standard deviation for customer age is 8.0 years. Using ? = 0.10, complete parts a and b below. a. Does the sample provide enough evidence to refute the age claim made by the sporting goods store? Determine the null and alternative hypotheses. H0: ? ? 39 H1: ? > 39 The z-test statistic is 2.97. (Round to two decimal places as needed.) The critical z-score(s) is(are) ____. (Round to two decimal places as needed. Use a comma to separate answers as needed.)
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The null hypothesis (H₀) is that the average age of customers is 39 or less, and the alternative hypothesis (H₁) is that the average age of customers is greater than 39. H₀: μ ≤ 39 H₁: μ > 39 Now, we need to find the critical z-score using the given Show more…
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