It is of note that the constraints in the primal are of the ‘‘6’’ type and they are of the ‘‘P’’ type instead in the dual.
Furthermore, the coefficients and constants of the primal and its dual are also exchanged.
As proved, the maximum solution of z in the primal problem is actually equal to the minimum solution of w in the dual problem.
The concept of duality is used in many fields, such as mathematics, engineering, and computer sciences.
It could significantly simplify problems by the so-called duality transformation.