商店有蓝书包42个，黄书包30个。共卖出35个，还剩多少个书包?2{8u7l;j
算式：提示2B1y+X7{3Q3z7{5i2{8u7l;j
答；还剩-~+[5C+];Q3J8M3@)g8W4Q个书包2{8u7l;j