The distance between A and B is 500 meters, and a total of 51 trees are planted from the beginning to the end. What is the average distance between every two trees?
甲、乙两地相距500米，从头到尾一共栽了51棵树，平均每两棵树之间的距离是多少米？
<gadget id="calculator">51 - 1</gadget>
<output>50</output>

<gadget id="calculator">500 / 50</gadget>
<output>10</output>

<result>10</result>