| $$ \begin{aligned}\frac{50^4}{36^4}& \xlongequal{ }\frac{6250000}{1679616} \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}} \frac{ 6250000 : \color{orangered}{ 16 } }{ 1679616 : \color{orangered}{ 16 }} \xlongequal{ } \\[1 em] & \xlongequal{ }\frac{390625}{104976}\end{aligned} $$ | |
| ① | Divide both the top and bottom numbers by $ \color{orangered}{ 16 } $. |