A recent study found that the average credit score for employed American adults is 702.5. A...

A recent study found that the average credit score for employed American adults is 702.5. A credit analyst wonders if this number is actually different for working millenials. In a random sample of 15 employed millenials, their sample mean credit score was 715.2 with a sample standard deviation of 83. Assume that credit scores of the population are normally distributed.

(a) Conduct the appropriate test to determine if millenials have a different credit score at the α = 0.05 level of significance using the critical region method. Verify all necessary assumptions and clearly state your hypotheses, test statistic, critical values, and conclusion.
(b) Construct a 95% confidence interval for the population mean credit score. Does this interval confirm the results of the hypothesis test? Explain.

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orchestra answered 1 year ago

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