A project can be completed by A alone in 5 days (1/3), and B alone can complete it in 10 days. How many days will it take for two people to work together?
一项工程，甲独做5天完成这项工程的(1/3)，乙独做10天完成．两人合做，需要多少天完成？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/3) / 5</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(1/15) + (1/10)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">1 / (1/6)</gadget>
<output>6</output>

<result>6</result>