A job alone takes 12 days, B alone takes 18 days, and C alone takes 24 days. This work is done by A for a certain number of days first, and then B will continue to do it. The number of days that B does is three times the number of days that A does, and then C continues to do it. The number of days that C does is twice the number of days that B does. Finally This job is done. How many days did it take in total?
一件工作，甲独做要12天，乙独做要18天，丙独做要24天．这件工作由甲先做了若干天，然后由乙接着做，乙做的天数是甲做的天数的3倍，再由丙接着做，丙做的天数是乙做的天数的2倍，终于做完了这件工作．问总共用了多少天？
<gadget id="calculator">1 / 12</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">1 / 18</gadget>
<output>1/18 = around 0.055556</output>

<gadget id="calculator">(1/18) * 3</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 / 24</gadget>
<output>1/24 = around 0.041667</output>

<gadget id="calculator">(1/24) * 3 * 2</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/12) + (1/6) + (1/4)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / (1/2)</gadget>
<output>2</output>

<gadget id="calculator">3 * 2</gadget>
<output>6</output>

<gadget id="calculator">6 * 2</gadget>
<output>12</output>

<gadget id="calculator">2 + 6 + 12</gadget>
<output>20</output>

<result>20</result>