Đặt tính rồi tính ta được:
\(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{52}\\{17}\end{array}}\\\hline{\,\,\,35}\end{array}\) \(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{91}\\{84}\end{array}}\\\hline{\,\,\,\,\,\,7}\end{array}\) \(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{80}\\{12}\end{array}}\\\hline{\,\,\,68}\end{array}\) \(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{40}\\{31}\end{array}}\\\hline{\,\,\,\,\,\,9}\end{array}\)
\(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{70}\\{\,\,2}\end{array}}\\\hline{\,\,\,68}\end{array}\) \(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{40}\\{\,\,5}\end{array}}\\\hline{\,\,\,35}\end{array}\) \(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{90}\\{81}\end{array}}\\\hline{\,\,\,\,\,\,9}\end{array}\) \(\begin{array}{*{20}{c}}{ - \begin{array}{*{20}{c}}{30}\\{23}\end{array}}\\\hline{\,\,\,\,\,\,7}\end{array}\)
