What is the average age of students in a class with 25 students, if the ages are 18, 20, 21, 18, 19, 22, 20, 19, 17, 21, 18, 20, 19, 22, 21, 20, 19, 17, 19, 20, 21, 19, 18, 20, 19?
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What is the simplified form of the mixed number 3 1/2 when expressed as an improper fraction?
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Find the derivative of f(x) = 3x^2 + 5sin(x) - 2ln(x + 1).