Two road construction teams jointly build a highway. Team A has built 21% of the total length, and team B has built 56 kilometers. At this time, the two teams have built 61% of the total length. How many kilometers is the total length of this road?
两个修路队合修一条公路，甲队已修了全长的21%，乙队修了56千米，这时两队共修了全长的61%，这条公路全长多少千米？
<gadget id="calculator">61 / 100</gadget>
<output>61/100 = around 0.61</output>

<gadget id="calculator">21 / 100</gadget>
<output>21/100 = around 0.21</output>

<gadget id="calculator">(61/100) - (21/100)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">56 / (2/5)</gadget>
<output>140</output>

<result>140</result>