Marketing to targeted age groups has become a standard method of advertising, even in movie theater advertising. Advertisers use computer software to track the demographics of moviegoers and then decide on the type of products to advertise before a particular movie. One statistic that might be of interest is how frequently adults with children under 18 attend movies as compared to those without children. Suppose that a theater database is used to randomly select 1000 adult ticket purchasers. These adults are then surveyed and asked whether they were frequent moviegoers—that is, do they attend movies 12 or more times a year? The results are shown in the table:

a. Is there a significant difference in the population proportions of frequent moviegoers in these two demographic groups? Use α = .01.

b. Why would a statistically significant difference in these population proportions be of practical importance to the advertiser?