For a leather jacket, if you get a 10% discount, you can make a profit of 215 yuan; if you get a 20% discount, you will lose 125 yuan. So how much is the purchase price of this leather jacket?
一件皮衣，如果打九折，可以赢利215元；如果打八折，就要亏损125元．那么这件皮衣的进价是多少元？
<gadget id="calculator">215 + 125</gadget>
<output>340</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">340 / (1/10)</gadget>
<output>3_400</output>

<gadget id="calculator">3_400 * (4/5)</gadget>
<output>2_720</output>

<gadget id="calculator">2_720 + 125</gadget>
<output>2_845</output>

<result>2_845</result>