Trees are planted on both sides of a road. A total of 50 trees are cut and one tree is planted every 5 meters (both ends are planted). How long is the road in meters?
在一条道路的两旁栽树，一共裁了50棵树，每隔5米栽一棵(两端都栽)，这条路长多少米．
<gadget id="calculator">50 / 2</gadget>
<output>25</output>

<gadget id="calculator">25 - 1</gadget>
<output>24</output>

<gadget id="calculator">24 * 5</gadget>
<output>120</output>

<result>120</result>