Question

On a recent mathematics test, the mean score was 75 and the standard deviation was 5.
Jhon got 93. Would his mark be considered an outlier if the marks were normally distributed? Explain your answer ?

Answer 1

$z=\frac{93-75}{5}=3.6\\ \text{We can treat any data value with a z-score}\\ \text{ less than -2 or greater than 2 as an outlier}$