After the price of a DVD player has been reduced (1/5), the current price is 400 yuan. How much is the original price?
一种影碟机降价(1/5)后，现在售价400元，原价多少元？
<gadget id="calculator">1 / 5</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">400 / (4/5)</gadget>
<output>500</output>

<result>500</result>