Sunshine Supermarket brought in 28 bags of flour, 25 kilograms each, and after selling some of them, there were 300 kilograms left. How many kilograms were sold?
阳光超市运进28袋面粉，每袋25千克，卖了一部分后还剩300千克，卖了多少千克？
<gadget id="calculator">25 * 28</gadget>
<output>700</output>

<gadget id="calculator">700 - 300</gadget>
<output>400</output>

<result>400</result>