The original price of a commodity is 400 yuan, and now it is sold at a 20% discount. What is the current price?
一件商品原价400元，现在打八折销售，现价是多少．
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

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

<result>320</result>