Đặt tính rồi tính: 34 567 + 12 345

\[\begin{array}{l} + \begin{array}{*{20}{c}}{34\,\,567}\\{\underline {12\,\,345} }\end{array}\\\,\,\,\,46\,\,912\end{array}\]

     \[\begin{array}{l} - \begin{array}{*{20}{c}}{98\,\,765}\\{\underline {43\,\,210} }\end{array}\\\,\,\,\,55\,\,555\end{array}\]

\[\begin{array}{l} - \begin{array}{*{20}{c}}{23\,\,456}\\{\underline {12\,\,345} }\end{array}\\\,\,\,\,\,11\,\,111\end{array}\]