Scores for men on the verbal portion of the SAT-I test are normally distributed with a mean of 509 and a standard deviation of 112.

Question

(a) If 1 man is randomly selected, find the probability that his score is at least 579.

(b) If 13 men are randomly selected, find the probability that their mean score is at least 579.

Answer 1

you can play around at

http://davidmlane.com/hyperstat/z_table.html

and do all kinds of neat Z-table stuff. Just enter your mean and std and you can see the areas (probabilities) for various kinds of calculations.