A road of 8.5 kilometers has been built, and 4.1 kilometers have been repaired. How many kilometers is less than the unrepaired road?
修一段8.5千米的路，已修了4.1千米，比未修的少多少千米？
<gadget id="calculator">8.5 - 4.1 - 4.1</gadget>
<output>0.3</output>

<result>0.3</result>