tính 999 - 888

\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{999}\\{888}\end{array}} \\\,\,\,\,111\end{array}\)

\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{871}\\{\,\,\,30}\end{array}} \\\,\,\,\,841\end{array}\)

\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{672}\\{511}\end{array}} \\\,\,\,\,161\end{array}\)

\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{618}\\{502}\end{array}} \\\,\,\,\,116\end{array}\)

\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{873}\\{\,\,\,51}\end{array}} \\\,\,\,\,822\end{array}\)

\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{172}\\{\,\,\,52}\end{array}} \\\,\,\,\,120\end{array}\)