The selling price of a piece of clothing is 700 yuan, and its profit rate is 40%. Find the cost price of this clothing.
一件服装的售价是700元，其盈利率为40%，求这件服装的成本价．
<gadget id="calculator">40 / 100</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">1 + (2/5)</gadget>
<output>7/5 = around 1.4</output>

<gadget id="calculator">700 / (7/5)</gadget>
<output>500</output>

<result>500</result>