There are two boxes of apples. If you take 4 kilograms from the first box and put them in the second box, the weight of the two boxes will be the same. How much is the weight of the first box of apples than the second box?
有两箱苹果，如果从第一箱中拿4千克放到第二箱，两箱就一样重了，原来第一箱苹果比第二箱苹果重多少千克？
<gadget id="calculator">4 * 2</gadget>
<output>8</output>

<result>8</result>