A car dealership interviewed every driver who came onto their lot on Tuesday. This produced the following results: there were 42 people who owned trucks and 87 people who owned cars. If 14 people owned both a truck and a car and 5 people owned neither, how many people were interviewed?

Question

anonymous · Answer

Figure out the total number of car and truck owners. Now consider: If someone owned both, they were counted twice in the total. If someone owned neither, they were never included in either category. Since you are being asked how many PEOPLE (and not just car or truck owners) were on the lot, You need to adjust the total to reflect the people counted twice and not at all.