650 x 100/120
$${\mathtt{650}}{\mathtt{\,\times\,}}\left({\frac{{\mathtt{100}}}{{\mathtt{120}}}}\right) = {\frac{{\mathtt{1\,625}}}{{\mathtt{3}}}} = {\mathtt{541.666\: \!666\: \!666\: \!666\: \!666\: \!7}}$$