# Question: The librarian at the local elementary school claims that on

The librarian at the local elementary school claims that, on average, the books in the library are more than 20 years old. To test this claim, a student takes a sample of n = 30 books and records the publication date for each. The sample produces an average age of µ = 23.8 years with a variance of s2 = 67.5.

Use this sample to conduct a one-tailed test with a = .01 to determine whether the average age of the library books is significantly greater than 20 years (m . 20).

Use this sample to conduct a one-tailed test with a = .01 to determine whether the average age of the library books is significantly greater than 20 years (m . 20).

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