Xingfu Village plans to build a 15-kilometer-long "immigration road". Team A needs 10 months to complete the training alone, and team B needs 15 months to complete the training alone. How many months can the joint training of the two teams be completed?
幸福村计划修一条15千米长的"移民公路"．甲队单独修需要10个月完成，乙队单独修需要15个月完成．两队合修几个月可以完成？
<gadget id="calculator">1 / 10</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">1 / 15</gadget>
<output>1/15 = around 0.066667</output>

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

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

<result>6</result>