Question

Three refineries with daily capacities of 6, 5, and 8 million gallons, respectively, supply three distribution areas with daily demands of 4, 8, and 7 million gallons, respectively. Gasoline is transported to the three distribution areas through a network of pipelines. The transportation cost is 10 cents per 1000 gallons per pipeline mile. The following table gives the mileage between the refineries and the distribution areas. Refinery 1 is not connected to distribution area 3.

Refinery	Distribution Area
	1	2	3
1	120	180	-
2	300	100	80
3	200	250	120

(a) Construct the associated transportation model using Northwest-corner method (7 pts), Least-cost method (8 pts) and Vogel approximation method (10 pts).
(b) Determine the optimum shipping schedule in the network (25 pts).

Answer 1