To build a road, 25% of the total length was repaired in the first month, and 2/5 of the total length was repaired in the second month. It is known that the repair in the second month is 3 kilometers longer than the first month. What is the total length of this road? rice? (column equation solution)
修一条公路，第一月修了全长的25%，第二个月修了全长的(2/5)，已知第二月比第一月多修3千米，这条公路全长多少千米？(列方程解答)
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(2/5) - (1/4)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">3 / (3/20)</gadget>
<output>20</output>

<result>20</result>