If you get a 10% discount on a piece of clothing, you can still get a profit of 200 yuan. If you get a 20% discount, you will lose 100 yuan. What is the cost price of this piece of clothing?
一件衣服如果打九折优惠，仍可获取200元的利润，如果打八折就要亏损100元，这件衣服成本价是多少元？
<gadget id="calculator">200 + 100</gadget>
<output>300</output>

<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

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

<gadget id="calculator">(9/10) - (4/5)</gadget>
<output>1/10 = around 0.1</output>

<gadget id="calculator">300 / (1/10)</gadget>
<output>3_000</output>

<gadget id="calculator">3_000 * (9/10)</gadget>
<output>2_700</output>

<gadget id="calculator">2_700 - 200</gadget>
<output>2_500</output>

<result>2_500</result>