To build a road, 20% of the total length is repaired in the first week, 25% of the total length is repaired in the second week, 480 meters are repaired in the third week, and there are 70 meters left. How long is the total length of this road?
修一条路，第一周修全长的20%，第二周修全长的25%，第三周修了480米，还剩70米，这条路全长多少米？
<gadget id="calculator">480 + 70</gadget>
<output>550</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

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

<gadget id="calculator">1 - (1/5) - (1/4)</gadget>
<output>11/20 = around 0.55</output>

<gadget id="calculator">550 / (11/20)</gadget>
<output>1_000</output>

<result>1_000</result>