The engineering team repairs a road and completes 15% of the whole project in 3 days. How many days will it take to complete the road? (Solve with ratio)
工程队修一条公路，开工3天正好完成全工程的15%，照这样修完这条公路还需多少天？(用比例解)
<gadget id="calculator">15 / 100</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">1 - (3/20)</gadget>
<output>17/20 = around 0.85</output>

<gadget id="calculator">3 * (17/20)</gadget>
<output>51/20 = around 2.55</output>

<gadget id="calculator">(51/20) / 0.15</gadget>
<output>17</output>

<result>17</result>