To build a (9/10) kilometer canal, and (1/6) of it was repaired in 3 days. According to this calculation, how many days will this canal be completed?
修一条(9/10)千米的水渠，3天修了它的(1/6)，照这样计算，这条水渠几天修完？
<gadget id="calculator">1 / 6</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">(1/6) / 3</gadget>
<output>1/18 = around 0.055556</output>

<gadget id="calculator">1 / (1/18)</gadget>
<output>18</output>

<result>18</result>