11. (10 points) A triangular plot of land has sides measuring 198 meters, 180 meters, and 210 meters. Trees are to be planted at equal distances along the three sides, with each tree 6 meters apart, and one tree is to be planted at each corner. How many trees will be planted in total.
【Solution】Solution: $(198+180+210) \div 6$
$$
\begin{array}{l}
=588 \div 6 \\
=98 \text { (trees)}
\end{array}
$$

Answer: A total of 98 trees need to be planted.
Therefore, the answer is: 98.