Решим примеры:
1) \begin{array}{@{}c@{\,}c@{,}c} & 2 & 7 \\ + & 6 & 8 \\ \hline & 9 & 5 \\ \end{array} \quad 27 + 68 = 95
2) \begin{array}{@{}c@{\,}c@{,}c} & 6 & 1 \\ - & 3 & 7 \\ \hline & 2 & 4 \\ \end{array} \quad 61 - 37 = 24
3) \begin{array}{@{}c@{\,}c@{,}c} & 5 & 6 \\ + & 4 & 4 \\ \hline & 1 & 0 & 0 \\ \end{array} \quad 56 + 44 = 100
4) \begin{array}{@{}c@{\,}c@{,}c} & 9 & 0 \\ - & 3 & 7 \\ \hline & 5 & 3 \\ \end{array} \quad 90 - 37 = 53
5) \begin{array}{@{}c@{\,}c@{,}c} & 1 & 9 \\ + & 2 & 8 \\ \hline & 4 & 7 \\ \end{array} \quad 19 + 28 = 47
6) \begin{array}{@{}c@{\,}c@{,}c} & 7 & 0 \\ + & 2 & 7 \\ \hline & 9 & 7 \\ \end{array} \quad 70 + 27 = 97
7) \begin{array}{@{}c@{\,}c@{,}c} & 8 & 4 \\ - & 7 & 9 \\ \hline & 0 & 5 \\ \end{array} \quad 84 - 79 = 5