If a tree is planted every 10 meters on both sides of a 100-meter road, how many trees should be planted in total?
一条100米的路两边每隔10米种一棵树，一共需要种多少棵树．
<gadget id="calculator">100 / 10</gadget>
<output>10</output>

<gadget id="calculator">10 + 1</gadget>
<output>11</output>

<gadget id="calculator">11 * 2</gadget>
<output>22</output>

<result>22</result>