batch of parts can be completed by A and B in 12 days of cooperation. After a few days of cooperation, B asks for leave due to something, and B only completes (3/10) of the total task at this time. A continued to work, and it took 14 days from the beginning to the completion of the task. How many days did A and B cooperate?
一批零件，甲、乙两人合作12天可以完成，他们合作若干天后，乙因事情请假，乙这时只完成了总任务的(3/10)．甲继续做，从开始到完任务用了14天，甲、乙合作了几天？
<gadget id="calculator">3 / 10</gadget>
<output>3/10 = around 0.3</output>

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

<gadget id="calculator">1 - (3/10)</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">(7/10) / 14</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">(1/12) - (1/20)</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">(3/10) / (1/30)</gadget>
<output>9</output>

<result>9</result>