Given:
Width is one third of length
Let length is "l"
Then width is:
[tex]w=\frac{l}{3}[/tex]If the width is 8 then length is:
[tex]\begin{gathered} w=8 \\ w=\frac{l}{3} \\ 8=\frac{l}{3} \\ l=8\times3 \\ l=24\text{ inches} \end{gathered}[/tex]length of rectangle is 24 inches.