Are people who live at higher altitudes slimmer?
Random samples were obtained for 125 adults living in Denver, Colorado (the Mile High City), and 150 adults living in New Orleans, Louisiana (where the mean elevation is zero feet above sea level). Using body mass index as a measure of obesity, 38 of those living in Denver and 61 of those living in New Orleans were classified as obese.
Is there any evidence to suggest that the people living in Denver are thinner? That is, is there any evidence to suggest that the proportion of adults classified as obese in Denver is less than the proportion of adults classified as obese in New Orleans? Use a = 0.05.