project can be completed in 8 days by two engineering teams A and B, and A alone can complete it in 12 days. If it is done by B alone, how many days will it take to complete it?
一项工程，甲、乙两个工程队合做8天可以完成，甲独做12天完成，如果由乙队独做，需要几天才能完成？
<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>