For a batch of goods, the price is reduced by 20% for the first time, and the price is reduced by 20% for the second time. What is the price at this time?
一批货物，第一次降价20%，第二次降价20%，这时的价格是原价的多少
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 - (1/5)</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">(4/5) * (4/5)</gadget>
<output>16/25 = around 0.64</output>

<result>16/25 = around 0.64</result>