There is an even row of poplar trees beside the road. An old man is walking along the road. It took him 10 minutes to walk from the first tree to the sixth tree. At this speed, he walked for 20 minutes. How many trees have you reached?
公路旁均匀地载着一排杨树，一位老人在公路旁散步，他从第1棵树走到第6棵树用了10分钟，照这样的速度，他走了20分钟，从第1棵走到了第多少棵．
<gadget id="calculator">6 - 1</gadget>
<output>5</output>

<gadget id="calculator">10 / 5</gadget>
<output>2</output>

<gadget id="calculator">20 / 2</gadget>
<output>10</output>

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

<result>11</result>