SOLUTION: I need help with this question. The scores for math test #3 were normally distributed. If 15 students had a mean score of 74.8% and a standard deviation of 7.57, how many students

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Question 970103: I need help with this question. The scores for math test #3 were normally distributed. If 15 students had a mean score of 74.8% and a standard deviation of 7.57, how many students scored above an 85%?
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Find the z score.
z=%2885-74.8%29%2F7.57=1.347
Find the probability associated with that z score.
P=0.9111
So scores above 85% would have a probability of 1-0.9111=0.0889
Out of the 15 students,
15%280.0889%29=1.33=1 student would have that score.
One student