A Quiz Consists of 15 Multiple Choice Questions

Short Answer

A quiz consists of 15 multiple choice questions. Each question has 5 choices, with exactly one correct choice. A student, totally unprepared for the quiz, guesses on each of the 15 questions.
How many questions should the student expect to answer correctly?
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What is the standard deviation of the number of questions answered correctly?
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If at least 9 questions must be answered correctly to pass the quiz, what is the chance the student passes?
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