z-score = (x-mean)/sd
1 = (48-m)/s
s = 48-m
s+m = 48 , #1
-1/2 = (36-m)/s
(-1/2)s = 36-m
-s = 72 - 2m
2m - s = 72 , #2
add #1 and #2
3m = 120
m = 40
then s+40 = 48
s = 8
mean = 40 , SD = 8
In a population of exam scores,a score of X= 48 corresponds to z= 1 and a score of X= 36 corresponds to z= -.50. Find the mean and standard deviation for the population?
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