## Algebra 2 (1st Edition)

The mean of $n$ numbers is the sum of the numbers divided by $n$. The median of $n$ is the middle number of the numbers when they are in order (and the mean of the middle $2$ numbers if $n$ is even). The mode of $n$ numbers is the number or numbers that appear(s) most frequently. Hence here the mean: $\frac{14+15+16+17+18+ 20+ 20}{7}=17.143$. The median is the average of the middle of the sequence $14,15,16,17,18, 20, 20$, which is: $17$. The mode is $20$.