The following data gives the number of miles per gallon for a random sample of U.S. cars vs. Japanese cars. We would like to test the hypothesis that Japanese cars get better mileage than U.S. cars at an alpha level of 0.01. US | Japanese 18 | 24 15 | 27 16 | 27 16 | 25 17 | 31 15 | 30 14 | 24 16 | 19 16 | 28 15 | 23 a) State the null and alternative hypotheses b) Check the assumptions and conditions. Are they satisfied? Give your histograms for the nearly normal condition (use 5 bins). c) Determine the critical value t*. d) Calculate the t statistic. e) State the result of the hypothesis test. What can you conclude?
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S cars is equal to the mean mileage for Japanese cars. Alternative Hypothesis: The mean mileage for Japanese cars is greater than the mean mileage for U.S cars. **Step 2:** Assumptions and Conditions: Show more…
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