老师拿70元去买书，买了7套故事书，每套9元，还剩多少元？0c+D2r6U/Z3h-Q5l;t'[;K7b8O
算式：提示,U+y5?.z9p:{:N0c+D2r6U/Z3h-Q5l;t'[;K7b8O
答；还剩-K9H6x7k8l4T)v'B元。0c+D2r6U/Z3h-Q5l;t'[;K7b8O