The upper fence and the lower fence are known as the upper limits and lower limits respectively. The upper fence and lower fence can be computed below
[tex]\begin{gathered} Q1=11 \\ Q3=15 \\ Interquartile\text{ range = 15-11=4} \\ \text{Lower fence=}Q1-1.5(4)=11-6=5 \\ \text{upper fence=}Q3+1.5(4)=15+6=21 \end{gathered}[/tex]
