Сумма чисел:
6 + 4 = 10
60 + 40 = 100
30 + 5 = 35
70 + 0 = 70
Разность чисел:
6 − 2 = 4
60 − 40 = 20
30 − 5 = 25
70 − 0 = 70
Вычисления:
6 + 4 = 10
​​​​​​​6 − 4 = 2
60 + 40 = 100
$\begin{array}{r}\begin{array}{r}+\end{array}\underline{\begin{array}{r}60\\ 40\end{array}}\\ \begin{array}{r}100\end{array}\end{array}$
60 − 40 = 20
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}60\\ 40\end{array}}\\ \begin{array}{r}20\end{array}\end{array}$
30 + 5 = 35
30 − 5 = 25
70 + 0 = 70
70 − 0 =70