There is a highway that Team A can complete in 15 days alone, and Team B can complete it in 10 days. If the two teams work together, how many days can they complete?
有一条公路，甲队单独修15天可以完成，乙队单独修10天可以完成，如果两队合修多少天可以完成？
<gadget id="calculator">1 / 15</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>