20% of a road has been repaired, and 30 kilometers have been repaired. How many kilometers is the road?
一段公路，已修了20%，修了30千米，公路有多少千米．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">30 / (1/5)</gadget>
<output>150</output>

<result>150</result>