The price of a coat is 400 yuan, and you can get (1/4) profit after selling it. How much is the purchase price of this coat?
一件上衣售价400元，售出后可得(1/4)的利润．这件上衣的进价是多少元？
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">1 + (1/4)</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">400 / (5/4)</gadget>
<output>320</output>

<result>320</result>