[tex]\bf \cfrac{4}{7}\div \cfrac{13}{28}\implies \cfrac{4}{~~\begin{matrix} 7\\[-0.7em]\cline{1-1}\\[-5pt]\end{matrix}~~ }\cdot \cfrac{\stackrel{4}{~~\begin{matrix} 28 \\[-0.7em]\cline{1-1}\\[-5pt]\end{matrix}~~}}{13}\implies \cfrac{16}{13}\implies 1\frac{3}{13}[/tex]
