4000 * 20 = 80000
 
5000 * 30 = 150000
 
160 * 500 − 17412 : 3 = 80000 − 5804 = 74196
$\begin{array}{r}\begin{array}{r}\times \end{array}\underline{\begin{array}{r}\mathrm{160 }\\ \mathrm{500 }\end{array}}\\ \begin{array}{r}80000\end{array}\end{array}$
$\begin{array}{cc}\begin{array}{l}\underset{¯}{\phantom{0}}17412\\ \phantom{0}\underset{¯}{15}\\ \phantom{0}\underset{¯}{\phantom{0}}24\\ \phantom{00}\underset{¯}{24}\\ \phantom{000}\underset{¯}{\phantom{0}}1\\ \phantom{0000}\underset{¯}{0}\\ \phantom{000}\underset{¯}{\phantom{0}}12\\ \phantom{0000}\underset{¯}{12}\\ \phantom{00000}0\end{array}& \begin{array}{l}\overline{)3}\\ \overline{\overline{)5804}}\end{array}\end{array}$
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}80000\\ 5804\end{array}}\\ \begin{array}{r}74196\end{array}\end{array}$