It takes 60 days for project team A to complete the construction of a citizen fitness square alone, and 40 days for project team B to complete it alone. How many days will it take if two engineering teams, A and B, work together?
建设一个市民健身运动广场，甲工程队单独完成需60天，乙工程队单独完成需要40天．如果甲、乙两工程队合建，需要多少天？
<gadget id="calculator">1 / 60</gadget>
<output>1/60 = around 0.016667</output>

<gadget id="calculator">1 / 40</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">(1/60) + (1/40)</gadget>
<output>1/24 = around 0.041667</output>

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

<result>24</result>