Chapter 8.4, Problem 19BSC

Testing Hypotheses. In Exercises 9-24, assume that a simple random sample has been selected and test the given claim. Unless specified by your instructor, use either the P-value method or the critical value method for testing hypotheses. Identify the null and alternative hypotheses, test statistic, P-value (or range of P-values), critical value(s), and state the final conclusion that addresses the original claim.

19. Years in College lasted below arc the numbers of years it took for a random sample of college students to cam bachelor’s degrees (based on data from the National Center for Education Statistics). Use a 0.01 significance level to test the claim that for all college students, the mean time required to earn a bachelor’s degree is greater than 4.0 years. Is there anything about the data that would suggest that the conclusion might not be valid?

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