ANSWER
[tex]IQR=13[/tex]EXPLANATION
The interquartile range can be found by finding the difference between the first quartile, Q1, and the third quartile, Q3.
That is:
[tex]IQR=Q3-Q1[/tex]Therefore, the interquartile range is:
[tex]\begin{gathered} IQR=81-68 \\ IQR=13 \end{gathered}[/tex]