What is the number of ways to arrange 5 books on a shelf, out of a total of 8 books?
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What is the average age of the students in a class if the ages of 30 students are 12, 13, 14, 11, 12, 13, 15, 12, 11, 13, 14, 12, 13, 14, 11, 12, 13, 15, 12, 11, 13, 14, 12, 13, 14, 11, 12, 13, 15, and 12?
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Math question: Solve the equation x^3 - 3x^2 + 2x - 1 = 0.