# Question: According to the Centers for Disease Control and Prevention average

According to the Centers for Disease Control and Prevention, average life expectancy in the United States has risen to 77.6 years (source: cnn.com). It has been suggested that residents in rural areas of the Southwest have a shorter life span than the general population. In a random sample of 250 recently deceased residents of the rural Southwest, the average life span was 75.9 years with a sample standard deviation of 9.8 years. Is the sample evidence sufficient to reject the null hypothesis shown below? Use a significance level of .05. H0: μ > 77.6 (The average life expectancy for residents of the rural Southwest is at least as long as the national average.) Ha: μ < 77.6 (The average life expectancy for residents of the rural Southwest is shorter than the national average.)

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