One college sent another a report saying that 119 students took Calculus I in a Fall semester. The report notes that during the next term, 96 of these students took Calculus II, 53 of them took Discrete Mathematics, and 39 of them took Physics-with-Calculus II. The report also says that 38 of the students took both Calculus II and Discrete Mathematics, 31 of the students took both Discrete Mathematics and Physics II, 32 of the students took both Calculus II and Physics II, and 22 of the students took all three courses. We examine the report and sense an error is present. Why?