The owner of a clothing store buys 500 pairs of socks at a price of 3 yuan per pair, and the original retail price is 4 yuan. Because it was too expensive, no one bought it, so the boss decided to sell it at 20% off the retail price, sold 60%, and sold the rest at 30% off the original retail price. Please calculate how much profit you make when you sell out 500 pairs of socks
服装店老板买进500双袜子，每双进价3元，原定零售价是4元．因为太贵，没人买，老板决定按零售价八折出售，卖了60%，剩下的又按原零售价的七折售完．请你算一下，卖完着500双袜子时盈利多少元
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">60 / 100</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">500 * (3/5)</gadget>
<output>300</output>

<gadget id="calculator">4 * (4/5) * 300</gadget>
<output>960</output>

<gadget id="calculator">70 / 100</gadget>
<output>7/10 = around 0.7</output>

<gadget id="calculator">500 - 300</gadget>
<output>200</output>

<gadget id="calculator">4 * (7/10) * 200</gadget>
<output>560</output>

<gadget id="calculator">960 + 560</gadget>
<output>1_520</output>

<gadget id="calculator">500 * 3</gadget>
<output>1_500</output>

<gadget id="calculator">1_520 - 1_500</gadget>
<output>20</output>

<result>20</result>