It has been 5 days to build a road of 540 kilometers, and there are 40 kilometers left. How many kilometers are repaired per day on average?
修一条公路540千米，已经修了5天，还剩40千米，平均每天修多少千米？
<gadget id="calculator">540 - 40</gadget>
<output>500</output>

<gadget id="calculator">500 / 5</gadget>
<output>100</output>

<result>100</result>