An instructor in a large lecture class discovered at the end of the semester that the total points scored by the students in his class were approximately Normal with a mean of 530 and a standard deviation of 80. If 10% of the class must receive A’s (he grades on a curve), what is the lowest number of points for a student to get an A?
A.632
B.610
C. 428 Here is how to find the answer:
Z = (mean score)/SD
Find a table at the back of your statistics text titled something like “areas under normal distribution” to find the proportion/probability (.10) and its Z-score and insert the values into the equation above to find the raw score. lh;jh