There is a square vegetable field with a side length of 20 meters. In order to prevent livestock from entering and eating vegetables, a fence needs to be built around the perimeter. 40 poles need to be inserted at equal distances from the beginning to the end. How many meters are there between every two poles?
有一块边长是20米的正方形菜地，为了防止牲畜进去吃菜，要沿四周做一道篱笆，需从头到尾等距离插40根竿，每两根竿之间相距多少米？
<gadget id="calculator">4 / 40</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">20 * (1/10)</gadget>
<output>2</output>

<result>2</result>