To build a concrete road, team A needs 12 days to complete the work alone, team B takes 15 days to complete the work alone, team B builds the first 5 days, and the rest is jointly repaired by A and B. How many days will it take to complete?
修筑一条水泥路，甲队独修需12天完成，乙队独修15天完成，乙队先修5天后，剩下的由甲、乙合修，还要多少天才能完工？
<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">(1/15) * 5</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1 - (1/3)</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">(1/12) + (1/15)</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">(2/3) / (3/20)</gadget>
<output>40/9 = around 4.444444</output>

<result>40/9 = around 4.444444</result>