The garment factory has to process 1,500 sets of garments, and processed 40% of this batch of garments in the first 3 days. According to this calculation, how many days will it take to process this batch of garments?
服装厂要加工1500套服装，前3天共加工了这批服装的40%，照这样计算，这批服装还要加工多少天？
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">3 / (2/5)</gadget>
<output>15/2 = around 7.5</output>

<gadget id="calculator">(15/2) - 3</gadget>
<output>9/2 = around 4.5</output>

<result>9/2 = around 4.5</result>