Xiaoming bought some exercise books at the retail price for 48 yuan. If you buy at the wholesale price, each copy is 2 yuan cheaper, and you just buy 4 more copies. Q: How much is the retail price per copy?
小鸣用48元钱按零售价买了若干练习本．如果按批发价购买，每本便宜2元，恰好多买4本．问：零售价每本多少元？
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