6 + 8 + 4 = 18
17 − 4 − 3 = 10
9 + 2 − 4 = 7
12 + 13 + 14 = 39
41 − 1 + 30 = 70
60 − 10 + 50 = 100
Вычисления:
6 + 8 + 4 = 14 + 4 = 18
$\begin{array}{r}\begin{array}{r}+\end{array}\underline{\begin{array}{r}14\\ 4\end{array}}\\ \begin{array}{r}18\end{array}\end{array}$
17 − 4 − 3 = 13 − 3 = 10
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}17\\ 4\end{array}}\\ \begin{array}{r}13\end{array}\end{array}$
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}13\\ 3\end{array}}\\ \begin{array}{r}10\end{array}\end{array}$
9 + 2 − 4 = 11 − 4 = 7
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}11\\ 4\end{array}}\\ \begin{array}{r}7\end{array}\end{array}$
12 + 13 + 14 = 25 + 14 = 39
$\begin{array}{r}\begin{array}{r}+\end{array}\underline{\begin{array}{r}12\\ 13\end{array}}\\ \begin{array}{r}25\end{array}\end{array}$
$\begin{array}{r}\begin{array}{r}+\end{array}\underline{\begin{array}{r}25\\ 14\end{array}}\\ \begin{array}{r}39\end{array}\end{array}$
41 − 1 + 30 = 40 + 30 = 70
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}41\\ 1\end{array}}\\ \begin{array}{r}40\end{array}\end{array}$
$\begin{array}{r}\begin{array}{r}+\end{array}\underline{\begin{array}{r}40\\ 30\end{array}}\\ \begin{array}{r}70\end{array}\end{array}$
60 − 10 + 50 = 50 + 50 = 100
$\begin{array}{r}\begin{array}{r}-\end{array}\underline{\begin{array}{r}60\\ 10\end{array}}\\ \begin{array}{r}50\end{array}\end{array}$
$\begin{array}{r}\begin{array}{r}+\end{array}\underline{\begin{array}{r}50\\ 50\end{array}}\\ \begin{array}{r}100\end{array}\end{array}$