45% is what is 9

$$\underset{\,\,\,\,{\textcolor[rgb]{0.66,0.66,0.66}{\rightarrow {\mathtt{x}}}}}{{solve}}{\left(\begin{array}{l}\left({\frac{{\mathtt{45}}}{{\mathtt{100}}}}\right){\mathtt{\,\times\,}}{\mathtt{x}}={\mathtt{9}}\\ {\mathtt{45}}{\mathtt{\,\times\,}}{\mathtt{x}}={\mathtt{900}}\\ {\mathtt{x}}={\frac{{\mathtt{900}}}{{\mathtt{45}}}}\\ {\mathtt{x}}={\mathtt{20}}\end{array}\right)}$$