Plant trees on both sides of a 150-meter-long road, and plant one tree every 5 meters (both ends must be planted), how many trees need to be planted in total.
在150米长的路的两旁栽树，每隔5米栽一棵(两端都要栽)，一共需要栽多少棵树．
<gadget id="calculator">150 / 5</gadget>
<output>30</output>

<gadget id="calculator">30 + 1</gadget>
<output>31</output>

<gadget id="calculator">31 * 2</gadget>
<output>62</output>

<result>62</result>