(1/5) of the light bulbs produced by a certain factory are defective products. During the actual inspection, only (4/5) of them were found to be rejected, and (1/20) of the genuine products were also rejected as defective products , the remaining bulbs are all listed for sale, what percentage of the bulbs sold by the factory are defective?
某工厂生产的灯泡中有(1/5)是次品，实际检查时，只发现其中的(4/5)被剔除，另有(1/20)的正品也被误以为是次品而剔除，其余灯泡全部上市出售，那么该工厂出售的灯泡中次品所占的百分比是多少？
<gadget id="calculator">1 / 5</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">1 - (4/5)</gadget>
<output>1/5 = around 0.2</output>

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

<gadget id="calculator">1 - (1/20)</gadget>
<output>19/20 = around 0.95</output>

<gadget id="calculator">80 * (19/20)</gadget>
<output>76</output>

<gadget id="calculator">100 * (1/5) * (1/5)</gadget>
<output>4</output>

<gadget id="calculator">76 + 4</gadget>
<output>80</output>

<gadget id="calculator">(1/5) / 80</gadget>
<output>1/400 = around 0.0025</output>

<gadget id="calculator">100 * (1/5) * (1/400)</gadget>
<output>1/20 = around 0.05</output>

<result>1/20 = around 0.05</result>