The road repair team repaired a road, the full length (1/12) was repaired in the first week, and the full length (1/9) was repaired in the second week, exactly 2100m was repaired in two weeks. How long is this road?
修路队修一条公路，第一个星期修了全长的(1/12)，第二星期修了全长的(1/9)，两个星期正好修2100m，这条路有多长？
<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">1 / 9</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">(1/12) + (1/9)</gadget>
<output>7/36 = around 0.194444</output>

<gadget id="calculator">2_100 / (7/36)</gadget>
<output>10_800</output>

<result>10_800</result>