Câu hỏi:

Let $x$ be the number of type A cars and $y$ be the number of type B cars to rent. We have the following conditions: * Number of people: $20x + 10y \ge 100$ or $2x + y \ge 10$ * Number of goods: $0.5x + 2y \ge 6$ or $x + 4y \ge 12$ * The number of type A cars does not exceed 8: $0 \le x \le 8$ * The number of type B cars does not exceed 6: $0 \le y \le 6$ The objective function is the cost of renting a car: $C = 4x + 3y$ (million VND), we need to find the minimum value of $C$. Consider the options: * Option 1: Rent 5 type A cars and 0 type B cars: $x=5, y=0$. Check the condition: $2(5) + 0 = 10 \ge 10$ (true), $5 + 4(0) = 5 \ge 12$ (false). So this option is not satisfied. * Option 2: Rent 2 type A cars and 3 type B cars: $x=2, y=3$. Check the condition: $2(2) + 3 = 7 \ge 10$ (false). So this option is not satisfied. * Option 3: Rent 0 type A cars and 3 type B cars: $x=0, y=3$. Check the condition: $2(0) + 3 = 3 \ge 10$ (false). So this option is not satisfied. * Option 4: Rent 3 type A cars and 2 type B cars: $x=3, y=2$. Check the condition: $2(3) + 2 = 8 \ge 10$ (false). We need to rent more cars.