On a midterm exam, a particular class ended up with a mean raw score of 80 with a standard
deviation of 10. The distribution of grades in the class was approximately normal. If the teacher
wants to give A’s to the top 25th percentile (top 25%) of the class, what is the lowest raw score
you could get and still get an A on the exam? (Hint: go backwards from the probability to the Z
score.)

Question

On a midterm exam, a particular class ended up with a mean raw score of 80 with a standard 
deviation of 10. The distribution of grades in the class was approximately normal. If the teacher 
wants to give A’s to the top 25th percentile (top 25%) of the class, what is the lowest raw score 
you could get and still get an A on the exam? (Hint: go backwards from the probability to the Z 
score.)