A jacket is priced at a profit of 40%. During the National Day, it is sold at a discount of 20% off the original price, and each jacket can still earn a profit of 30 yuan. What is the cost price of this jacket?
一款上衣按40%的利润定价，国庆节期间，按原价打八折出售，每件上衣仍可获得利润30元，这款上衣的成本价是多少元？
<gadget id="calculator">80 / 100</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(2/5) * (4/5)</gadget>
<output>8/25 = around 0.32</output>

<gadget id="calculator">(8/25) - 1</gadget>
<output>-17/25 = around -0.68</output>

<gadget id="calculator">(4/5) + (-17/25)</gadget>
<output>3/25 = around 0.12</output>

<gadget id="calculator">30 / (3/25)</gadget>
<output>250</output>

<result>250</result>