Plant 101 trees on the side of the road, and the distance between them is 4 meters. Now only 51 trees are to be planted (both ends are planted), how many meters should their interval be changed?
在路的一旁种101棵树，它们的间隔是4米．现在要改为只种51棵树(两端都种)，它们的间隔应改为多少米？
<gadget id="calculator">101 - 1</gadget>
<output>100</output>

<gadget id="calculator">51 - 1</gadget>
<output>50</output>

<gadget id="calculator">4 / 50</gadget>
<output>2/25 = around 0.08</output>

<gadget id="calculator">100 * (2/25)</gadget>
<output>8</output>

<result>8</result>