There is a highway, team A needs 10 days to study alone, team B needs 12 days to study alone, and team C needs 15 days to study alone. Now let the three teams work together, but the middle team A withdrew to another construction site. As a result, it took 6 days to complete the road repair. After Team A withdrew, how many days did Team B and Team C work together to complete the training?
有一条公路，甲队独修需10天，乙队独修需12天，丙队独修需15天．现在让三个队合修，但中间甲队撤离到另外工地，结果一共用了6天把这条公路修完．当甲队撤出后，乙、丙两队又共同合修了几天才完成？
<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

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

<gadget id="calculator">(3/20) * 6</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">1 - (9/10)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/10) / (1/10)</gadget>
<output>1</output>

<gadget id="calculator">6 - 1</gadget>
<output>5</output>

<result>5</result>