posted by Tegan .
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.
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