<PRE><B>Question 890339</B>
you calculate the z score.


z score is equal to (x - m) / sd


x is the score of the student who was selected at random.


m is the mean.
s is the standard deviation.


if the score of the student was 78, the z score would be (78 - 78) / 6 = 0


if the score of the student was 100, the z score would be (100 - 78) / 6 = 22/6 = 3.67 rounded to 2 decimal places.


if the score of the student was 50, the z score would be (50 - 78) / 6 = -4.67 rounded to 2 decimal places.


the greatest probability is determined by looking up the z score in the z score table and determining what the probability is.


i would need to know what your possible answers are in order to help you with that.


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