If the container is a cube, every side is a square, so the length and the width are the same.
To get the number of gumballs based on the number of gumballs in one side, we can use the following equation
[tex]TotalGumballs=x^3[/tex]Where x is the number of gumballs along one side. So, replacing the total by 729 and solving for x, we get:
[tex]\begin{gathered} 729=x^3 \\ \sqrt[3]{729}=x \\ 9=x \end{gathered}[/tex]Answer: She counts 9 gumballs along one side of the container