Department store. A department store is planning its next advertising campaign. Since different publications are read by different market segments, they would like to know if they should be targeting...

Department store. A department store is planning its next advertising campaign. Since different publications are read by different market segments, they would like to know if they should be targeting specific age segments. The results of a marketing survey are summarized in the following table by Age and Shopping Frequency at their store.

Find the marginal distribution of Shopping Frequency