Suppose that distribution of the mid-term grades of the entire classes in the College follows N(78,36)....

Suppose that distribution of the mid-term grades of the entire classes in the College follows N(78,36).

(a) What is the proportion of students who received the grades less than 75?

(b) Suppose that there is a class with 50 students. What is the probability that the average grades of this class is less than 75?

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orchestra answered 1 year ago

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