The price of a commodity after a 20% discount is 320 yuan. What is the original price of this commodity?
一种商品八折后的价钱是320元，这种商品的原价是多少元．
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">320 / (4/5)</gadget>
<output>400</output>

<result>400</result>