The following is the frequency distribution of ages for a random sample of 20 students using the university's counselling service during the winter, 2016 term. \begin{tabular}{|cc|} \hline Age & Frequency W \hline \hline 18 & 5 Thline 19 & 6 W \hline 20 & 3 \hline 21 & 2 \hline 22 & 1 W \hline 23 & 1 W \hline 24 & 1 W \hline 26 & 1 Thline & $N=20$ \hline \end{tabular} SP.VS.780