1. Calculate in the most rational way

$$
12 \times 171+29 \times 9+171 \times 13+29 \times 16
$$
$$
\begin{aligned}
& 12 \times 171 + 29 \times 9 + 171 \times 13 + 29 \times 16 = \\
& = (171 \times 12 + 171 \times 13) + 29 \times 9 + 29 \times 16 = \\
& = 171 \times (12 + 13) + 29 \times (9 + 16) = \\
& = 171 \times 25 + 29 \times 25 = (171 + 29) \times 25 = \\
& = 200 \times 25 = 5000
\end{aligned}
$$

Answer: 5000.