Question

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?

Answer 1

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.