The road repair team repaired a section of road. On the first day (1/2) repaired this section of road, and on the second day (3/7) this section of road was repaired. What percentage of the road is left unrepaired?
修路队修一段公路，第一天修了这段路的(1/2)，第二天修了这段路的(3/7)，还剩几分之几没有修？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">(1/2) + (3/7)</gadget>
<output>13/14 = around 0.928571</output>

<gadget id="calculator">1 - (13/14)</gadget>
<output>1/14 = around 0.071429</output>

<result>1/14 = around 0.071429</result>