To produce a batch of parts, it is planned to produce 160 parts per day, which can be completed in 15 days, but the actual daily production exceeds 80 parts, how many days can it be completed in advance? (Solution by proportional method)
生产一批零件，计划每天生产160个，15天可以完成，实际每天超产80个，可以提前几天完成？(用比例方法解)
<gadget id="calculator">160 * 15</gadget>
<output>2_400</output>

<gadget id="calculator">80 * 15</gadget>
<output>1_200</output>

<gadget id="calculator">1_200 - 2_400</gadget>
<output>-1_200</output>

<gadget id="calculator">2_400 + (-1_200)</gadget>
<output>1_200</output>

<gadget id="calculator">160 + 80</gadget>
<output>240</output>

<gadget id="calculator">1_200 / 240</gadget>
<output>5</output>

<result>5</result>