Homework Help: statistics

Posted by Jen on Friday, September 25, 2009 at 10:29am.

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.

statistics - PsyDAG, Friday, September 25, 2009 at 11:44am
Mean is 2 SD below 88 and one above 79.

88 - 79 = 9 Therefore mean is 1/3 of that distance above 79 and 2/3 below 88.

Z = (x - μ)/SD

Substitute the values for Z, x and μ, and solve for the SD.

I hope this helps. Thanks for asking.

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