tính 72 + 28
Giải thích
\(\begin{array}{l}\underline { + \begin{array}{*{20}{c}}{72}\\{28}\end{array}} \,\,\,\,\\\,\,100\end{array}\) | \(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{42}\\{26}\end{array}} \\\,\,\,\,16\end{array}\) | \(\begin{array}{l}\underline { + \begin{array}{*{20}{c}}{36}\\{35}\end{array}} \\\,\,\,\,71\end{array}\) | \(\begin{array}{l}\underline { - \begin{array}{*{20}{c}}{43}\\{28}\end{array}} \\\,\,\,\,15\end{array}\) |