Question

Suppose grades in a class are given as percentages, with an average of 0.6, and a standard deviation of

0.2, while the “theoretical” numbers are, in the mind of this instructor would be 0.75 as average and 0.1

as standard deviation. Assuming these parameters reflect the instructor's expectations

Question 1

According to the “theoretical” model that the instructor has in mind, that is

N(μ,σ)=N (0.75,0.1) , a normal distribution with the given mean and standard deviation,

what is the probability that a student might score

1. less than 0.5

2. more than 0.9

Question 2

Having “corrected” the scores using the procedure described above, what is the “corrected” grade for a

student whose original score was 0.5 and for a student whose original score was 0.9?

Answer 1