The original price of a bicycle is 400 yuan. What is the price of this bicycle after a 20% discount?
一辆自行车原价400元，这辆车打八折后的价钱是多少元．
<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>