A vendor buys a batch of socks directly from the manufacturer. The purchase price is 20 yuan to buy 30 pairs. The vendor sells 10 pairs at a price of 12 yuan. The total profit is 800 yuan. How many pairs of the purchased socks are there?
某商贩直接从厂家进一批袜子，进价是20元买30双，商贩以12元10双的价钱卖出，共盈利800元，购进的这批袜子有多少双．
<gadget id="calculator">12 / 10</gadget>
<output>6/5 = around 1.2</output>

<gadget id="calculator">20 / 30</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">(6/5) - (2/3)</gadget>
<output>8/15 = around 0.533333</output>

<gadget id="calculator">800 / (8/15)</gadget>
<output>1_500</output>

<result>1_500</result>