mot doi san xuat co 18 cong nhan chia thanh hai to,trong do to mot co 10 nguoi trung binh moi nguoi an xuat duoc 52 san pham.Hoi trung binh moi nguoi cua to hai phai san xuat bao nhieu san pham de trung binh moi nguoi cua doi san xuat duoc 56 san pham ?