There is a 160-meter-long path in the park. If you want to plant trees from the beginning to the end of the path, a total of 21 trees will be planted. How many meters should you plant a tree?
公园里有一条160米长的小路，要在这条小路上从头到尾种树，一共种树21棵，那么每隔多少米就种一棵树？
<gadget id="calculator">21 - 1</gadget>
<output>20</output>

<gadget id="calculator">160 / 20</gadget>
<output>8</output>

<result>8</result>