A、B、C、D四个同学共同买了一张饭卡价值500元,办卡时由于C、D两位同学没钱,因此A同学为其垫上,后来由于暑假,A、B、D同学决定回家,C则继续留校,所以三人决定将饭卡给C,此时C同学需要分别退多少钱给他们三人?请详细说明解题思路,漏了一个条件（对不起）,暑假前卡里还剩420元
ice繁华Hs228
很简单,请不要看复杂的过程,从结果倒推,
就是说花了80元,平均每人花了20元,用整体法,A就支付375,自己花了20,就需要找355,B支付125,花了20
所以找105,D剩负20,那就向他要20,自己剩负20,这个问题的关键就在于自己花了的加上找回的等于自己一开始支付的
我们来看A 355+20=375
B 105+20=125
C 负20+20=0
D 负20+20=0
楼上所说的拆分其实不应该那样拆,因为如果要按比例拆分那么他们所花的钱也得是按比例花的,但他们都花了20元
有不明白的可以再追问
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