To build a road, 450 meters are built every day. After 27 days of repairing, there are still 250 meters to be completed. How long is the road?
修一条公路，每天修450米，修了27天后还有250米没有修完，这条公路长多少米？
<gadget id="calculator">450 * 27</gadget>
<output>12_150</output>

<gadget id="calculator">12_150 + 250</gadget>
<output>12_400</output>

<result>12_400</result>