1. Rift Valley Sand and Gravel Pit have contracted to provide topsoil for three residential housing developments.Topsoil can be supplied from three different "farms" as follows:

Farm Weekly capacity (cubic yards)

A 100

B 200

C 200

Demand for the topsoil generated by the construction projects is:

Project Weekly demand (cubic yards)

1. 50
2. 150
3. 300

The manager of the sand and gravel pit has estimated the cost per cubic yard to ship over each of the possible routes:

Cost per cubic yard (in Birr)

From Project #1 Project #2Project #3

Farm A 4 2 8

Farm B 5 1 9

Farm C 7 6 3

A. Formulate a balanced transportation problem in a transportation tableau

B. Find minimum transportation cost using Northwest corner, least cost and VAM methods