There are two cups of sugar water A and B. If 300g is taken from A and 200g is taken from B, the concentration of sugar water obtained after mixing is 36%. If the sugar water taken from A is 3 times that of B, then the sugar water obtained after mixing The concentration of sugar water is 30%, so what is the concentration of sugar water in A.
有两杯糖水A和B，如果从A中取出300g，B中取出200g混合后得到糖水的浓度为36%，如果从A中取出的糖水是B中取出的3倍，那么混合后得到的糖水的浓度为30%，那么原来A中的糖水浓度是多少．
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