(57 * 9 + 87) : 6 = (513 + 87) : 6 = 600 : 6 = 100
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}57\\ 9\end{array}}\\ 513\end{array}$
 
$\begin{array}{r}\begin{array}{r}+\end{array}\underline{\begin{array}{r}513\\ 87\end{array}}\\ \begin{array}{r}600\end{array}\end{array}$
 
$\begin{array}{cc}\begin{array}{l}\underset{¯}{\phantom{0}}600\\ \phantom{0}\underset{¯}{6}\\ \phantom{0}\underset{¯}{\phantom{0}}0\\ \phantom{00}\underset{¯}{0}\\ \phantom{00}\underset{¯}{\phantom{0}}0\\ \phantom{000}\underset{¯}{0}\\ \phantom{000}0\end{array}& \begin{array}{l}\overline{)6}\\ \overline{\overline{)100}}\end{array}\end{array}$
 
(648 : 4 − 78) * 4 = (162 − 78) * 4 = 84 * 4 = 336;
$\begin{array}{cc}\begin{array}{l}\underset{¯}{\phantom{0}}648\\ \phantom{0}\underset{¯}{4}\\ \underset{¯}{\phantom{0}}24\\ \phantom{0}\underset{¯}{24}\\ \phantom{00}\underset{¯}{\phantom{0}}8\\ \phantom{000}\underset{¯}{8}\\ \phantom{000}0\end{array}& \begin{array}{l}\overline{)4}\\ \overline{\overline{)162}}\end{array}\end{array}$
 
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}162\\ 78\end{array}}\\ \begin{array}{r}84\end{array}\end{array}$
 
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}84\\ 4\end{array}}\\ 336\end{array}$
 
(807 − 55 * 6) : 9 = (807 − 330) : 9 = 477 : 9 = 53
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}55\\ 6\end{array}}\\ 330\end{array}$
 
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}807\\ 330\end{array}}\\ \begin{array}{r}477\end{array}\end{array}$
 
$\begin{array}{cc}\begin{array}{l}\underset{¯}{\phantom{0}}477\\ \phantom{0}\underset{¯}{45}\\ \phantom{0}\underset{¯}{\phantom{0}}27\\ \phantom{00}\underset{¯}{27}\\ \phantom{000}0\end{array}& \begin{array}{l}\overline{)9}\\ \overline{\overline{)53}}\end{array}\end{array}$
 
(900 − 755 : 5) : 7 = (900 − 151) : 7 = 749 : 7 = 107
$\begin{array}{cc}\begin{array}{l}\underset{¯}{\phantom{0}}755\\ \phantom{0}\underset{¯}{5}\\ \underset{¯}{\phantom{0}}25\\ \phantom{0}\underset{¯}{25}\\ \phantom{00}\underset{¯}{\phantom{0}}5\\ \phantom{000}\underset{¯}{5}\\ \phantom{000}0\end{array}& \begin{array}{l}\overline{)5}\\ \overline{\overline{)151}}\end{array}\end{array}$
 
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}900\\ 151\end{array}}\\ \begin{array}{r}749\end{array}\end{array}$
 
$\begin{array}{cc}\begin{array}{l}\underset{¯}{\phantom{0}}749\\ \phantom{0}\underset{¯}{7}\\ \phantom{0}\underset{¯}{\phantom{0}}4\\ \phantom{00}\underset{¯}{0}\\ \phantom{0}\underset{¯}{\phantom{0}}49\\ \phantom{00}\underset{¯}{49}\\ \phantom{000}0\end{array}& \begin{array}{l}\overline{)7}\\ \overline{\overline{)107}}\end{array}\end{array}$
 
137 * 6 : 2 = 822 : 2 = 411
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}137\\ 6\end{array}}\\ 822\end{array}$
 
$\begin{array}{cc}\begin{array}{l}\underset{¯}{\phantom{0}}822\\ \phantom{0}\underset{¯}{8}\\ \phantom{0}\underset{¯}{\phantom{0}}2\\ \phantom{00}\underset{¯}{2}\\ \phantom{00}\underset{¯}{\phantom{0}}2\\ \phantom{000}\underset{¯}{2}\\ \phantom{000}0\end{array}& \begin{array}{l}\overline{)2}\\ \overline{\overline{)411}}\end{array}\end{array}$
 
219 : 3 * 8 = 73 * 8 = 584.
$\begin{array}{cc}\begin{array}{l}\underset{¯}{\phantom{0}}219\\ \phantom{0}\underset{¯}{21}\\ \phantom{00}\underset{¯}{\phantom{0}}9\\ \phantom{000}\underset{¯}{9}\\ \phantom{000}0\end{array}& \begin{array}{l}\overline{)3}\\ \overline{\overline{)73}}\end{array}\end{array}$
 
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}73\\ 8\end{array}}\\ 584\end{array}$