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有10张数字卡片,按如下图所示排成两列,请你左右任意调换一张卡片,使左、右两边各数之和相等。小朋友,该怎样调换呢?
There are 10 digital cards, arranged in two columns as shown below, please arbitrarily change a card so that the left and right sides of each sum of the same. Children, how to change it?