TeX source:
\begin{array}{rclcl} V &=& \dfrac{4}{3}\pi r^3 &\vert& :\dfrac{4}{3} : \pi \cr \dfrac{3V}{4\pi} &=& r^3 &\vert& \sqrt[3]{ } \cr \sqrt[3]{\dfrac{3V}{4\pi}} &=& r \end{array}