657 * 4 = 2628
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}657\\ 4\end{array}}\\ 2628\end{array}$
 
509 * 7 = 3563
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}509\\ 7\end{array}}\\ 3563\end{array}$
 
2193 * 5 = 10965
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}2193\\ 5\end{array}}\\ 10965\end{array}$
 
7640 * 8 = 61120
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}7640\\ 8\end{array}}\\ 61120\end{array}$
 
40018 * 9 = 360162
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}40018\\ 9\end{array}}\\ 360162\end{array}$
 
80700 * 6 = 484200
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}80700\\ 6\end{array}}\\ 484200\end{array}$
 
(9010 − 6235) * 9 = 2775 * 9 = 24975
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}9010\\ 6235\end{array}}\\ \begin{array}{r}2775\end{array}\end{array}$
 
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}2775\\ 9\end{array}}\\ 24975\end{array}$
 
8 * (4348 + 2062) = 8 * 6410 = 51280
$\begin{array}{r}\begin{array}{r}+\end{array}\underline{\begin{array}{r}4348\\ 2062\end{array}}\\ \begin{array}{r}6410\end{array}\end{array}$
 
$\begin{array}{r}\times \underset{¯}{\begin{array}{r}6410\\ 8\end{array}}\\ 51280\end{array}$