A computer is now priced at 3600 yuan after a price reduction (1/5). How much is the original price of this computer?
一台电脑，降价(1/5)后现在售价3600元，这台电脑原价多少元？
<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">3_600 / (4/5)</gadget>
<output>4_500</output>

<result>4_500</result>