To build a road, 40.8 meters were built on the first day, and 31.2 meters on the second day. What is the total length of this road?
修一条公路，第一天修了40.8米，第二天修了31.2米，问这条公路全长多少米？
<gadget id="calculator">40.8 + 31.2</gadget>
<output>72</output>

<result>72</result>