
Concept explainers
Textbook Prices, UCSB vs. CSUN (Example 16) The prices of a sample of books at University of California at Santa Barbara (UCSB) were obtained by statistics students Ricky Hernandez and Elizabeth Alamillo. Then the cost of books for the same subjects (at the same level) were obtained for California State University at Northridge (CSUN). Assume that the distribution of differences is Normal enough to proceed, and assume that the sampling was ran-dom. The data are at this text’s website.
First find both sample
Test the hypothesis that the population means are different, using a significance level of

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Introductory Statistics
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