This is an overlapping set. You can recognize these because it's possible to do two things at once, or neither, or just one; in this case it's wearing a jacket and/or a tie. Many people use Venn diagrams for these but Venn diagrams can be confusing. An Overlapping Set Table is much easier. Simply draw three vertical and three horizontal lines and then label them with the two possibilities and their opposites. Consult the attached image for an example. Then just fill in the parts of the table. The boxes in every row and column should add to the total.
In this problem, we aren't given any numbers; rather we're given percents. No biggie. Just pretend that the total number of people is 100 and then treat the percents we're given as though they're actually totals. This allows us to fill out the table as illustrated below. Therefore the answer is E.
Attachments
jackets and ties.jpg [ 22.3 KiB  Viewed 468 times ]
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