The price of a commodity is 500 yuan, the price is first reduced by 20%, and then the price is increased by 20%, what is the price at this time?
一种商品售价500元，先降价20%，再涨价20%，这时售价是多少元．
<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">1 + (1/5)</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">500 * (4/5) * (6/5)</gadget>
<output>480</output>

<result>480</result>