Question

In: Statistics and Probability

Professor Harde assumes that test scores are normally distributed and wants to grade "on the curve."...

Professor Harde assumes that test scores are normally distributed and wants to grade "on the curve." The mean score was 58, with a standard deviation of 14. (Round your answers to the nearest whole number.)

(a) If she wants 15% of the students to receive an A, find the minimum score to receive an A.


(b) If she wants 22% of the students to receive a B, find the minimum score to receive a B.

Solutions

Expert Solution

Ans : The mean score and standard deviation

Let X = test scores , X follows normal distribution (given)

a) If she wants 15% of the students to receive an A, then the minimum score to receive an A is

  

Therefore  the minimum score to receive an A is 73

b)

If she wants 22% of the students to receive a B, find the minimum score to receive a B is

Therefore the minimum score to receive a B is 69.

orchestra answered 1 year ago
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