It is known that 13/6 ounces are needed for 1 wall.
So with 26/3 ounces, she can create walls equal to:
[tex]\begin{gathered} \frac{\frac{26}{3}}{\frac{13}{6}}=\frac{26}{3}\times\frac{6}{13} \\ =\frac{13\times2}{3}\times\frac{3\times2}{13} \\ =2\times2 \\ =4 \end{gathered}[/tex]Hence 4 walls can be created with 26/3 ounces of pretzel.