Build a road, 6 days to build this road (2/5). According to this calculation, how many days will it take to complete the road?
修筑一条公路，6天修筑了这条公路的(2/5)．照这样计算，修完这条公路要多少天？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/5) / 6</gadget>
<output>1/15 = around 0.066667</output>

<gadget id="calculator">1 / (1/15)</gadget>
<output>15</output>

<result>15</result>