In a batch of parts produced by a certain factory, the number of second-class products is 16% of the number of first-class products. How many percent are second-class products less than first-class products?
某工厂生产的一批零件中，二等品数量是一等品数量的16%，二等品比一等品少百分之几？
<gadget id="calculator">16 / 100</gadget>
<output>4/25 = around 0.16</output>

<gadget id="calculator">1 - (4/25)</gadget>
<output>21/25 = around 0.84</output>

<result>21/25 = around 0.84</result>