The road construction team wants to build a road, and has already repaired 80% of the total length. At this time, there is still 40 kilometers to the end. How many kilometers is this road?
修路队要修一条公路，已经修了全长的80%，这时距终点还有40千米．这条公路长多少千米？
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 - (4/5)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">40 / (1/5)</gadget>
<output>200</output>

<result>200</result>