A product is priced at 320 yuan after a 20% price reduction. What is the original price of this product?
一件商品，降价20%后售价是320元，这件商品原价是多少元？
<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">320 / (4/5)</gadget>
<output>400</output>

<result>400</result>