49

Решение:

1.
\( \begin{array}{c} +345 \\ +559 \\ ule{0.7cm}{0.01cm} \\ 904 \end{array} \)

2.
\( \begin{array}{c} -716 \\ -127 \\ ule{0.7cm}{0.01cm} \\ 589 \end{array} \)

3.
\( \begin{array}{c} -805 \\ -345 \\ ule{0.7cm}{0.01cm} \\ 460 \end{array} \)

1.
\( \begin{array}{c} \times 217 \\ \times 4 \\ ule{0.7cm}{0.01cm} \\ 868 \end{array} \)

2.
\( \begin{array}{c} \times 329 \\ \times 3 \\ ule{0.7cm}{0.01cm} \\ 987 \end{array} \)

3.
\( \begin{array}{c} \times 409 \\ \times 2 \\ ule{0.7cm}{0.01cm} \\ 818 \end{array} \)

Ответ:
1. \( \frac{+345}{+559} \)
2. \( \frac{-716}{-127} \)
3. \( \frac{-805}{-345} \)
1. \( \frac{\times 217}{ \times 4} \)
2. \( \frac{\times 329}{ \times 3} \)
3. \( \frac{\times 409}{ \times 2} \)