tính 52 – 18

\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{52}\\{18}\end{array}} \\\,\,\,\,34\end{array}\)

\(\begin{array}{l}\underline { + \begin{array}{*{20}{c}}{68}\\{13}\end{array}} \\\,\,\,\,81\end{array}\)

\(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{80}\\{66}\end{array}} \\\,\,\,\,14\end{array}\)

\(\begin{array}{l}\underline { + \begin{array}{*{20}{c}}{35}\\{57}\end{array}} \\\,\,\,\,92\end{array}\)