Problem 108
Over 60% of the people who fly to Normal, Illinois, do so on American Airlines. Hence, most people prefer American to any other airline.
Solution
This statement is trying to say that normal, Illinois is the basis for a general population nationwide, even though it is just one place. So, the 60 percent of people flying American Airlines to normal, Illinois should not be represented nationwide, because there are other airlines to be considered that the population may fly on.