A highway was repaired for 29 kilometers on the first day, and the full length (3/7) remains. How much of the full length was repaired on the first day?
一条公路第一天修了29千米，还剩全长的(3/7)，第一天修了全长的多少．
<gadget id="calculator">3 / 7</gadget>
<output>3/7 = around 0.428571</output>

<gadget id="calculator">1 - (3/7)</gadget>
<output>4/7 = around 0.571429</output>

<result>4/7 = around 0.571429</result>