[tex]\bf \cfrac{~~\frac{3}{5}-\frac{1}{7}~~}{\frac{1}{35}}\implies \cfrac{~~\stackrel{\textit{using an LCD of 35}}{\frac{(7)3-(5)1}{35}}~~}{\frac{1}{35}}\implies \cfrac{~~\frac{21-5}{35}~~}{\frac{1}{35}}\implies \cfrac{~~\frac{16}{35}~~}{\frac{1}{35}} \\\\\\ \cfrac{16}{~~\begin{matrix} 35 \\[-0.7em]\cline{1-1}\\[-5pt]\end{matrix}~~}\cdot \cfrac{~~\begin{matrix} 35 \\[-0.7em]\cline{1-1}\\[-5pt]\end{matrix}~~}{1}\implies 16[/tex]