10. (10 points) Two buildings in a residential area are 220 meters apart. After planting 10 trees at equal distances between them, the distance between the 1st tree and the 6th tree is $\qquad$ meters.
【Answer】Solution: $220 \div(10+1) \times(6-1)$
$$
\begin{array}{l}
=20 \times 5 \\
=100 \text { (m) }
\end{array}
$$

Answer: The distance between the 1st tree and the 6th tree is 100 meters. Therefore, the answer is: 100.