Add the length of all three tables, as shown below
[tex]\begin{gathered} (4+\frac{1}{2})+4+(2+\frac{1}{2})=10+(\frac{1}{2}+\frac{1}{2})=10+(\frac{2}{2})=10+1=11 \\ \Rightarrow(4+\frac{1}{2})+4+(2+\frac{1}{2})=11 \end{gathered}[/tex]
The answer is 11 ft.
