SOLUTION: How to do this: Scores on a test are normally distributed with a mean of 78 and a standard deviation of 6. A student is selected at random. Which has the greatest probability?

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Question 890339: How to do this:
Scores on a test are normally distributed with a mean of 78 and a standard deviation of 6. A student is selected at random. Which has the greatest probability?
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
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.