[tex]\bf \begin{array}{|c|ll} \cline{1-1} \textit{a\% of b}\\ \cline{1-1} \\ \left( \cfrac{a}{100} \right)\cdot b \\\\ \cline{1-1} \end{array}~\hspace{5em}\stackrel{\textit{7.5\% of x}}{\left(\cfrac{7.5}{100} \right)}x \\\\[-0.35em] ~\dotfill\\\\ \cfrac{7.5}{100}\cdot \cfrac{10}{10}\implies \cfrac{75}{1000}\implies \cfrac{3}{40}[/tex]
