927 − 792 = 135
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}927\\ 792\end{array}}\\ \begin{array}{r}135\end{array}\end{array}$
 
308 − 195 = 113
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}308\\ 195\end{array}}\\ \begin{array}{r}113\end{array}\end{array}$
 
658 + 342 = 1000
$\begin{array}{r}\begin{array}{r}+\end{array}\underline{\begin{array}{r}658\\ 342\end{array}}\\ \begin{array}{r}1000\end{array}\end{array}$
 
389 + 572 = 961
$\begin{array}{r}\begin{array}{r}+\end{array}\underline{\begin{array}{r}389\\ 572\end{array}}\\ \begin{array}{r}961\end{array}\end{array}$
 
288 * 3 = 864
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}288\\ 3\end{array}}\\ 864\end{array}$
 
109 * 9 = 981
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}109\\ 9\end{array}}\\ 981\end{array}$
 
912 : 4 = 228
$\begin{array}{cc}\begin{array}{l}\underset{¯}{\phantom{0}}912\\ \phantom{0}\underset{¯}{8}\\ \underset{¯}{\phantom{0}}11\\ \phantom{00}\underset{¯}{8}\\ \phantom{0}\underset{¯}{\phantom{0}}32\\ \phantom{00}\underset{¯}{32}\\ \phantom{000}0\end{array}& \begin{array}{l}\overline{)4}\\ \overline{\overline{)228}}\end{array}\end{array}$
 
654 : 6 = 109
$\begin{array}{cc}\begin{array}{l}\underset{¯}{\phantom{0}}654\\ \phantom{0}\underset{¯}{6}\\ \phantom{0}\underset{¯}{\phantom{0}}5\\ \phantom{00}\underset{¯}{0}\\ \phantom{0}\underset{¯}{\phantom{0}}54\\ \phantom{00}\underset{¯}{54}\\ \phantom{000}0\end{array}& \begin{array}{l}\overline{)6}\\ \overline{\overline{)109}}\end{array}\end{array}$