The Nanjing Railway Team wants to repair a section of railway, and 4.05 kilometers have been repaired, and the rest is 2.45 kilometers less than the repaired one. How long is this railway in kilometers?
南京铁路队要修一段铁路，已经修好了4.05千米，剩下的比修好的少2.45千米．这段铁路全长多少千米？
<gadget id="calculator">4.05 - 2.45</gadget>
<output>1.6</output>

<gadget id="calculator">1.6 + 4.05</gadget>
<output>5.65</output>

<result>5.65</result>