Buying a mobile phone online is 320 yuan cheaper than buying it in a store, which is 20% cheaper. How much does this phone sell online?
一款手机从网上购买比商店购买便宜320元，便宜20%．这款手机网上卖多少钱？
<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">320 / (1/5)</gadget>
<output>1_600</output>

<gadget id="calculator">1_600 - 320</gadget>
<output>1_280</output>

<result>1_280</result>