Suppose the mean grade for a statistics midterm exam was 75, with a standard deviation of...

Suppose the mean grade for a statistics midterm exam was 75, with a standard deviation of 10. Assume that your grades were normally distributed.

a. What percentage of students received at least an 90?

e. If 2 students failed the exam, i.e. their grades were less than 60, how many students took the test? Hint: First focus on p(x<60).

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orchestra answered 1 year ago

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