To build a 3,000-meter road, engineering team A can complete the repair in 10 days, and engineering team B can complete the repair in 15 days. Both engineering teams, A and B, can repair it at the same time. How many days can it be completed?
修一条3000米公路，甲工程队10天修完，乙工程队15天修完，甲乙两个工程队同时修，几天可以修完？
<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>