If the price of a product is increased by 20% first and then reduced by 20%, how much lower is the price of the product than the original price?
一种商品，如果先提价20%，再降价20%，那么该商品的售价和原来相比较比原价低多少
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

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

<gadget id="calculator">1 * (6/5) * (4/5)</gadget>
<output>24/25 = around 0.96</output>

<gadget id="calculator">1 - (24/25)</gadget>
<output>1/25 = around 0.04</output>

<result>1/25 = around 0.04</result>