# Question: In a 1997 study people were observed for about 10

In a 1997 study, people were observed for about 10 seconds in public places, such as malls and restaurants, to determine whether they smiled during the randomly chosen 10-second interval. The table shows the results for comparing males and females.

a. Find and compare the sample percentages of women who were smiling and men who were smiling.

b. Treat this as though it were a random sample, and test whether there are differences in the proportion of men and the proportion of women who smile. Use a significance level of 0.05.

c. Explain why there is such a small p-value even though there is such a small difference in sample percentages.

a. Find and compare the sample percentages of women who were smiling and men who were smiling.

b. Treat this as though it were a random sample, and test whether there are differences in the proportion of men and the proportion of women who smile. Use a significance level of 0.05.

c. Explain why there is such a small p-value even though there is such a small difference in sample percentages.

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