If the question is how many firms have income over $20m, then you can calculate this by 276 - 103 - 52 = 121
This is because the three options are mutually exclusive - each advertising firm must fall in exactly one category (no more, no less) and so the total number across all the categories must equal the number of firms surveyed.
Mar 8th, 2015
Did you know? You can earn $20 for every friend you invite to Studypool!