Maria and Juana recieved scores of 82 and 65, respectively. If these score are equivalent to z-scores of 1.6 and -0.2, respectively,what are the mean and the standard deviation of the scores of all the students who took the examination?

Answer 1

z = (x - m)/s, where s is the standard deviation and m is the mean.

so you end up with 2 equations in 2 unknowns
1.6 = (82-m)/s
1.6s = 82 - m -----> 10m + 16s = 820

-.2 = (65-m)/s
-.2s = 65 - m ---> 10m - 2s = 650
easy to solve for m and s

Answer 2

34