If a piece of clothing is sold at 10% off the original price, a profit of 100 yuan can be made, and if it is sold at 20% off the original price, a profit of 70 yuan can be made. How much is the original price of this kind of clothes?
一件衣服，如果按原售价打九折出售，可获利100元，如果按原售价打八折出售，可获利70元．这种衣服原价是多少元？
<gadget id="calculator">100 - 70</gadget>
<output>30</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">30 / (1/10)</gadget>
<output>300</output>

<result>300</result>