The engineering team repaired a section of road. The original plan was to repair 3.2 kilometers per day, and the repair was completed in 15 days. In fact, the extra 0.8 kilometers per day was repaired. How many days can the task be completed? (Solve with ratio)
工程队修一段公路，原计划每天修3.2千米，15天修完，实际每天多修0.8千米，几天能完成任务？(用比例解)
<gadget id="calculator">3.2 * 15</gadget>
<output>48</output>

<gadget id="calculator">3.2 + 0.8</gadget>
<output>4</output>

<gadget id="calculator">48 / 4</gadget>
<output>12</output>

<result>12</result>