Abstract
This paper deals with stationary and cyclical production planning model where multi-goods are produced with a single line. Our model is formulated by a standard form of linear programming (LP). We present a necessary and sufficient condition concerning variable cost and demand of each good under which the optimal solution of LP satisfies each inequality constraint by equality. When we utilize above condition further, we can decide whether optimal solution in regular cyclical productions is also global optimal solution even in all production orders including non-cyclical production.
