Lenovo Computer Company held a "May 1st discount". The current price is 20% lower than before. Xiaohong's mother bought a computer for 2,800 yuan. How much is the original price of this computer?
联想电脑公司举行"五一优惠"，现在的售价比原来降低20%，小红的妈妈用2800元买了一台电脑，这台电脑原价是多少元？
<gadget id="calculator">20 / 100</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">2_800 / (4/5)</gadget>
<output>3_500</output>

<result>3_500</result>