simplex method (Big M Method)

4. Four foods x1, X2, X3, X4 are to be produced. x1 contains 2 units of calories, no vitamins and costs P40 per unit. X2 contains no calorie, 2 units of vitamins and costs P100. xz contains 1 unit of calorie, 1 unit of vitamins and costs P120 per unit. x4 contains 3 units of calorie, 2 units of vitamins and costs P150 per unit. The minimum calorie requirement is 15 units and the minimum vitamin requirement is 8 units. How much of each food should be produced to satisfy these requirements and to minimize the total cost