| $$ \begin{aligned}\frac{58800}{98280}& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}} \frac{ 58800 : \color{orangered}{ 840 } }{ 98280 : \color{orangered}{ 840 }} \xlongequal{ } \\[1 em] & \xlongequal{ }\frac{70}{117}\end{aligned} $$ | |
| ① | Divide both the top and bottom numbers by $ \color{orangered}{ 840 } $. |