[tex]\bf 7\div \cfrac{2}{3}\implies 7\cdot \cfrac{3}{2}\implies \cfrac{7\cdot 3}{2}\implies \cfrac{21}{2}\implies 10\frac{1}{2}~~\checkmark \\\\[-0.35em] \rule{34em}{0.25pt}\\\\ \stackrel{\textit{so, what happened to Mario?}}{7\div \cfrac{2}{3}\implies \cfrac{7}{1}\div \cfrac{2}{3}}\implies \stackrel{\boxed{?}}{\cfrac{1}{7}}\cdot \cfrac{3}{2}\implies \cfrac{3}{14}~~\bigotimes[/tex]
he ended up multiplying the 7 by the 2 for some reason.
and an explanation could be he used the reciprocal of both numbers mistakenly.