Plant trees on one side of a 100-meter-long straight road (planting at both ends). Originally, a tree pit was dug every 4 meters, but now it is changed to a tree pit every 5 meters. How many tree pits can be dug again? How many
在一条长100米的直路一边植树(两头都植)，原来每4米挖一个树坑，现改为每隔5米挖一个树坑，共有几个树坑可以不必重挖？多少
<gadget id="calculator">100 / 20</gadget>
<output>5</output>

<gadget id="calculator">5 + 1</gadget>
<output>6</output>

<result>6</result>