a project. It takes 12 days for worker A to complete it alone, and 8 days for worker A and B to complete it together. How many days will it take for worker B to complete it alone?
一项工程．甲工人单独完成需要12天，甲乙二人合作8天就可以完成，如让乙单独完成需要多少天？
<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

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

<gadget id="calculator">(1/8) - (1/12)</gadget>
<output>1/24 = around 0.041667</output>

<gadget id="calculator">1 / (1/24)</gadget>
<output>24</output>

<result>24</result>