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In: Statistics and Probability

John is going to take a quiz with 10 MC questions. Each question has only one...

  1. John is going to take a quiz with 10 MC questions. Each question has only one correct answer out of 4 choices. Suppose John simply answer each question by random guess,
    1. (5) What is the probability of have 5 questions answered correctly?
    2. (5) What is the expected number and standard deviation of the questions answered correctly?
    3. (10) If a correct answer counts for 1 point and a wrong answer causes 1 point deduction,
      1. list out all the possible points of this quiz.
      2. what is the expected points of John’s quiz?

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