The engineering team plans to build a road of 4.5 kilometers per day and complete it in 20 days. The actual repair is 6 kilometers per day. How many days can it be completed? (Solve with ratio)
工程队修一条公路，计划每天4.5千米，20天完成，实际每天修6千米，实际几天可修完？(用比例解)
<gadget id="calculator">4.5 * 20</gadget>
<output>90</output>

<gadget id="calculator">90 / 6</gadget>
<output>15</output>

<result>15</result>