# statistics

In a population of exam scores, a score of x=88 corresponds to z=+2.00 and a score of x=79 corresponds to z=-1.00. Find the mean and standard deviation for the population.

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1. z/sigma = score - mean

2 sigma = 88 - mean
-sigma = 79 - mean

subtract second equation from first.
3 sigma = 9
sigma = 3 is the standard deviation

Use either equation to get the mean

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posted by drwls

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