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\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{55}\\{\,\,6}\end{array}} \\\,\,\,49\end{array}\)

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\[\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{31}\\{\,\,2}\end{array}} \\\,\,\,29\end{array}\]

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\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{31}\\{\,\,7}\end{array}} \\\,\,\,24\end{array}\)

\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{55}\\{\,\,8}\end{array}} \\\,\,\,47\end{array}\)

\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{77}\\{\,\,9}\end{array}} \\\,\,\,68\end{array}\)

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