To build a road, team A has built 400 meters, which is 20% less than team B. How many meters has team B built?
修一条路，甲队修了400米，比乙队少修20%，乙队修了多少米？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">400 / (4/5)</gadget>
<output>500</output>

<result>500</result>