To build a road, 20% of the total length was repaired in the first week, and 1/4 of the total length was repaired in the second week. A total of 900 meters was repaired in two weeks. How long is the road in meters?
修一条路，第一周修了全长的20%，第二周修了全长的(1/4)，两周一共修了900米，这条路长多少米．
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

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

<gadget id="calculator">(1/5) + (1/4)</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">900 / (9/20)</gadget>
<output>2_000</output>

<result>2_000</result>