To find the mean, add the scores and divide that sum by 5, the number of scores:

$\displaystyle\frac{\text{93 + 66 + 78 + 85 + 98}}{\text{5}}=\frac{{420}}{{5}}={84}\usepackage{cmbright}\Huge\$

To find the median, arrange the values in order from least to greatest and identify the middle value: 66, 78, 85, 93, 98. The median is 85.

The mean with a value of 84 is less than the median whose value is 85.