Problema Solution
in a set of 100 act scores, where the mean is 22 and the standard deviation is 3.32, how many scores are expected to be lower than 18.68?
Answer provided by our tutors
The Z-score is:
Z-score = (18.68-22)/3.32
Z-score = -1.
P(Z < -1) = 0.1587
Number of scores expected to be lower than 18.68 is 0.1587*100 =15.87 or approximately 16.