To process a batch of school uniforms, the original plan was to process 320 sets per day and finish in 60 days. In fact, in order to catch up with the time, we processed 25% more than the original plan every day. How many days can the task be completed in advance?
加工一批校服，原计划每天加工320套，60天完成，实际为了赶时间，每天比原计划多加工了25%，实际可提前几天完成任务？
<gadget id="calculator">320 * 60</gadget>
<output>19_200</output>

<gadget id="calculator">25 / 100</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 + (1/4)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">320 * (5/4)</gadget>
<output>400</output>

<gadget id="calculator">19_200 / 400</gadget>
<output>48</output>

<gadget id="calculator">60 - 48</gadget>
<output>12</output>

<result>12</result>