In a class test where the mean was 62% and the standard deviation 12.6%, Jan received 74%. What is her result a a z-score?

1 Answer
Mar 18, 2016

Z score means the number of standard deviations above (or below for negative) the mean.

Explanation:

#Z=(x-mean)/(sd)#

#Z=(74-62)/(12.6)=0.95#

Generally Z scores outside of [-2,2] are considered outliers. Since the 74% has a Z of 0.95, it's significantly above the mean but not overwhelmingly so.