A piece of clothing with an original price of 500 yuan in the Jiefang Road shopping mall is now sold at a 10% discount. If you have a VIP card, and you can sell it at 80% of the preferential price, then you only need how much yuan to buy this dress with the VIP card.
解放路商场原价为500元的一件衣服，现在按九折优惠出售．如果有贵宾卡，又可以按优惠价的80%出售，那么用贵宾卡买这件衣服的只需要多少元．
<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">500 * (9/10) * (4/5)</gadget>
<output>360</output>

<result>360</result>