There is a batch of apples in the fruit wholesale store, half of the original apples are sold on the first day, another 250 kilograms are purchased in the morning of the next day, and 400 kilograms are sold in the afternoon, leaving 220 kilograms. How many kilograms of apples are there in the fruit shop?
水果批发店有一批苹果，第一天卖出了原有苹果的一半，第二天上午又进货250千克，下午又卖出了400千克，还剩220千克．水果店原有苹果多少千克？
<gadget id="calculator">220 - 250</gadget>
<output>-30</output>

<gadget id="calculator">400 + (-30)</gadget>
<output>370</output>

<gadget id="calculator">370 / 0.5</gadget>
<output>740</output>

<result>740</result>