3. (9 points) Calculate using a simplified method (the process must be written)
(1) $25 \times 26 \times 8$
(2) $340 \times 40 \div 17$
(3) $440 \times 15+480 \times 15+79 \times 15+15$.
【Solution】Solution: (1) $25 \times 26 \times 8$
$$
\begin{array}{l}
=25 \times 8 \times 26 \\
=200 \times 26 \\
=5200
\end{array}
$$
(2) $340 \times 40 \div 17$
$$
\begin{array}{l}
=340 \div 17 \times 40 \\
=20 \times 40 \\
=800
\end{array}
$$
$$
\begin{aligned}
& \text { (3) } 440 \times 15+480 \times 15+79 \times 15+15 \\
= & (440+480+79+1) \times 15 \\
= & 1000 \times 15 \\
= & 15000
\end{aligned}
$$