Team A and Team B jointly build a road with a length of a meter. Team A repairs 12 meters per day, and Team B repairs 8 meters per day. How many days can they complete half of the road?
甲、乙两队共同修建一条长a米的公路，甲队每天修12米，乙队每天修8米，多少天能修完这条公路的一半？
<gadget id="calculator">1 / 40</gadget>
<output>1/40 = around 0.025</output>

<result>1/40 = around 0.025</result>