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In fact, the question has nothing to do with percentages: In a class of 40 students, 32 are business majors. Of the 24 students who passed the midterm examination, 18 are business majors. How many students in the class who are not business majors passed the examination? The use of percentages in this context makes the question sound more complicated to some, and detracts from the fact that it is just about elementary arithmetic. The same effect would be achieved by asking the question in a foreign language Dans une classe de 40 étudiants, 32 étudient en administration des affaires. The basic role of percentages (and communication tools in general) is to simplify complex information. If I want to be understood rather than confusing, I say that 27 of my 35 students passed the exam rather than say that the success rate was 77.1%. However with larger numbers, percentages give a better, simpler view: I would rather read that in the last election, voter turnout was 53% rather than to read that 4,421,628 of the 8,380,702 voters did vote; the latter formulation is still understandable though it is cumbersome. In our society, the people are so much bombarded by senseless data in the most complex form possible that they become innumerate. We then arrive at the paradoxical situation where percentages are tought at school and universities, though people should easily understand them by themselves in the Claude  


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