Add 8 trees equidistantly between the two trees, so that the distance between the first tree and the fifth tree is 20 meters, how many meters are the distance between the original two trees?
在两棵树中间等距离地增加8棵树，这样第1棵树与第5棵树相隔20米，原来的两棵树相距多少米？
<gadget id="calculator">5 - 1</gadget>
<output>4</output>

<gadget id="calculator">20 / 4</gadget>
<output>5</output>

<gadget id="calculator">8 + 1</gadget>
<output>9</output>

<gadget id="calculator">5 * 9</gadget>
<output>45</output>

<result>45</result>