An instructor gives a 100-point test in which the grades are approximately normally distributed. The mean...

An instructor gives a 100-point test in which the grades are approximately normally distributed. The mean is 65 points and the standard deviation is 12 points.

a. What is the lowest possible score to qualify in the top 5% of the scores?

b. If 500 students took the test, how many students received a score between 60 and 80 points?

( I hope the solution to the questions can be provided as well )

Expert Solution

orchestra answered 2 years ago

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An instructor gives a 100-point test in which the grades are approximately normally distributed. The mean...

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