supermarket held a shopping discount activity, which stipulated that if a purchase exceeds 500 yuan, a 10% discount will be given for the part below 500 yuan (including 500 yuan), and a 20% discount will be given for the part exceeding 500 yuan. Wang Rong went to the supermarket to buy a computer, and he had to pay a total of 3,130 yuan after the prescribed discount. How much is the original price of this computer?
某超市举行购物优惠活动，规定：如果一次购物超过500元，则其中500元以下部分(含500元)给予九折优惠，超过500元部分给予八折优惠．王荣到该超市购买了一台电脑，按规定优惠后共需付款3130元．这台电脑原来的标价是多少元？
<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">500 * (9/10)</gadget>
<output>450</output>

<gadget id="calculator">3_130 - 450</gadget>
<output>2_680</output>

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

<gadget id="calculator">2_680 / (4/5)</gadget>
<output>3_350</output>

<gadget id="calculator">3_350 + 500</gadget>
<output>3_850</output>

<result>3_850</result>