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In: Statistics and Probability

Suppose that the midterm score of a class is normally distributed with the mean of 68.2...

Suppose that the midterm score of a class is normally distributed with the mean of 68.2 points and the standard deviation of 11.3 points. Answer each question.

  1. (5 pts) Sketch the curve of the distribution representing the midterm score. Make sure to mark the mean and three standard deviations to either side of the mean.

  2. (10 pts) Find the probability that a randomly selected student has score at most 65.9

  3. (10 pts) To be in the top 20% of the class, you need to score what point?

d. (10 pts) What is the probability that the average score of 13 students is more than 87 points? explain details please if calculator is used

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