A section of road has been built for 40 days, 350 meters per day, and the repaired section is 30% less than the rest. Find the total length of this section of road.
修一段公路，已经修了40天，每天修350米，已修的比剩下的少全长的30%，求这段公路全长．
<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1 - (3/10) - (3/10)</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">40 / (2/5)</gadget>
<output>100</output>

<gadget id="calculator">350 * 100</gadget>
<output>35_000</output>

<result>35_000</result>