The road repair team rushed to repair a road and completed it in 4 days (2/5). At this speed, how many days will it take for the rest of the project to be completed?
修路队抢修一条公路，4天完成了(2/5)，照这样的速度，余下的工程还需要几天完成？
<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 - (2/5)</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">(2/5) / 4</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">(3/5) / (1/10)</gadget>
<output>6</output>

<result>6</result>