**Minimisation
Example**

Text:

The final product has a requirement that it must weigh exactly 150 kg. The two raw materials used are A, with a cost of $2 per unit, and B, with a cost of $8 per unit. At least 14 units of B and no more than 20 units of A must be used. Each unit of A weighs 5 kg; each unit of B weighs 10 kg. How much of each type of raw material should be used for each unit of final product if we wish to minimise cost ?

Definition of variables:

X_{1} = Number of units of product A

X_{2} = Number of units of product B

Objective function:

Constraints:

1.The total weight must be equal to 150 kg

2.No more than 20 units of A may be used

3.At least 14 units of B must be used

Non-negativity: