妈妈买上衣和裤子共用去79元,买上衣用去50元,买裤子用去多少元?7N9C+b,R:O-J/S*F1R0X
算式:提示:J*N(r7M*Q.w'Q1N6e+B7N9C+b,R:O-J/S*F1R0X
答:买裤子用去,S0`5R0c元。7N9C+b,R:O-J/S*F1R0X