Plant trees on one side of a 120-meter-long straight road (both ends are planted). It was originally planned to plant a tree every 4 meters. The tree pit has been dug. Instead, plant a tree every 6 meters. How many tree pits are there in total? Re-dig?
在一条长120米的直路的一边植树(两头都栽)，原来计划每4米种一棵树，树坑已挖好，改为每6米种一棵树，那么共有多少个树坑不需要重挖？
<gadget id="calculator">120 / 12</gadget>
<output>10</output>

<gadget id="calculator">10 + 1</gadget>
<output>11</output>

<result>11</result>