Let the company use x1 kg of cement and x2 kg of sand to make concrete bricks.
Cement cost squqre 20 per kg and sand cost □ 6 per kg.
∴ the total cost c = □(20x1+6x2)
This is a linear function which is to be minimized
Hence, it is an objective function.
Total weight of brick = (x1+x2)kg
Since, the weight of concrete bricks has to be at least 5 kg,
∴x1+x2≤5
Since concrete brick should contain minimum 4 kg of cement and not more than 2kg of sand,
x1≥4and0≤x2≤2
Hence, the given LPP can be formulated as:
Minimize c=20x1+6x2, subject to
x1+x2≥5,x1≥4,0≤x2≤2