A production team needs to process a batch of auto parts. The original plan is to process 400 pieces per day and complete the task in 18 days. Actually process 450 per day, how many days earlier than the original plan to complete the task?
一个生产小组，要加工一批汽车配件，原计划每天加工400个，18天完成任务．实际每天加工450个，这样比原计划提前几天完成任务？
<gadget id="calculator">18 / 450</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">400 * (1/25)</gadget>
<output>16</output>

<gadget id="calculator">18 - 16</gadget>
<output>2</output>

<result>2</result>