It takes 16 days for A to complete a project alone, and B’s work efficiency is three times that of A. How many days can the two cooperate to complete half of the project?
一项工程，甲单独完成需要16天，乙的工作效率是甲的3倍，两人合作几天能完成这项工程的一半？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 16</gadget>
<output>1/16 = around 0.0625</output>

<gadget id="calculator">(1/16) * 3</gadget>
<output>3/16 = around 0.1875</output>

<gadget id="calculator">(1/16) + (3/16)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/2) / (1/4)</gadget>
<output>2</output>

<result>2</result>