A road is 570 meters long, has been repaired for 8 days, and there are 250 meters left. How many meters are repaired per day on average?
一条路长570米，已经修了8天，还剩250米．平均每天修多少米？
<gadget id="calculator">570 - 250</gadget>
<output>320</output>

<gadget id="calculator">320 / 8</gadget>
<output>40</output>

<result>40</result>