In a given population, a score of X= 88 corresponds to z= +2.00 and a score of X= 79 corresponds to

vasorasy8 2022-07-06 Answered
In a given population, 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.

I know how to find X and z-scores as well as how to plug things into the z-score formula, but I'm not sure how to solve this one. It says to sketch out a distribution table and find where the mean and SD fall on it, but I'm not sure how to do that.
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Answers (1)

Jordan Mcpherson
Answered 2022-07-07 Author has 16 answers
A z score is just a way of saying that it's that many standard deviations above or below the mean. Since they've given you two values and the z scores you can figure it out. Let m , s denote the mean and standard deviation of the distribution. Then,
X 1 X 2 = 9 = z 1 z 2 = 3 s
So the s = 3 and m = X 1 2 s = 82.
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