An electronics factory produces a batch of calculators. It originally planned to produce 400 pieces per day and complete the task in 30 days. After the introduction of technology, 15% can be completed in the first 3 days. According to this calculation, how many days can the task be completed?
某电子厂生产一批计算器，原计划每天生产400只30天完成任务，引进技术后，前3天可以完成15%，照这样计算，几天可以完成任务？
<gadget id="calculator">15 / 100</gadget>
<output>3/20 = around 0.15</output>

<gadget id="calculator">(3/20) / 3</gadget>
<output>1/20 = around 0.05</output>

<gadget id="calculator">1 / (1/20)</gadget>
<output>20</output>

<result>20</result>