posted by Jen .
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.
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.