Reconsider the previous exercise.
a. Suppose that the study had included 100 people of each sex. Determine the test statistic and p-value for testing whether the proportions who are satisfied with their attractiveness diff er significantly between the two sexes using a theory-based test.
b. Now suppose that the study had included 500 people of each sex. Reanswer (a).

c. Summarize what this reveals about the role of sample sizes in a two-proportion z-test.

Data from previous exercise

A survey conducted by the Gallup organization in 1999 asked American adults whether they are satisfied with their physical attractiveness or wish they could be more attractive. The survey found that 71% of women and 81% of men responded that they were satisfied with their attractiveness.