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The median separates the data set into two equal groups, one consisting of values which are greater than the median, and one consisting of values which are less than the median. The median gives a different view of the central tendency of the data set. In this particular problem, the values of the mean and the median are approximately equal. Either measure could be use to represent the central tendency of the data set. However, since the mean can be use in hypothesis testing, the mean is more useful. Hypothesis Test: The null and alternative hypotheses are: Null hypothesis: (Claim) Alternative hypothesis: Critical values: Based on the hypotheses shown above, the test is a two-tailed test. The z-statistic can be used because the sample size is greater than 30. The critical values for a two-tailed z-test, with  = 0.05, are -1.96 and 1.96. This test will reject the null hypothesis if the test value is less than -1.96, or greater than 1.96 Test value: The test valu

e is calculated as: The p-value for this test statistic is 0.0297 Decision: The test value is less than the negative critical value, -1.96, so the decision is to reject the null hypothesis. Using the p-value method, the null hypothesis is rejected since the p-value of the test statistic, 0.0287, is less than the level of significance, 0.05. Summary: The hypothesis test indicates that there is sufficient evidence at the 0.05 level of significance to reject the boss’s claim that the average body fat is equal to 20%. Based on what you have learned from your research on regression analysis and correlation, answer the following questions about the Body Fat Versus Weight data set: Your analysis is now complete, and you are ready to report your findings to your boss. In one paragraph, summarize your results by explaining your findings from the statistical measures, hypothesis test, and regression analysis of body fat and weight for the 252 men attending Silver’s Gym.