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Using Excel to Formulate and Solve Transportation Problems

Using Excel to Formulate and Using Excel to Formulate and Solve Transportation ProblemsSolve Transportation Problems To formulate and solve a transportation

problem using Excel, two separate tables need to be entered on a spreadsheet

The first one is the parameter table The second is a solution table, containing

the quantities to distribute from each source to each destination

Two separate tables Two separate tables

Functional constraints -1Functional constraints -1

The two types of functional constraints need to be included in the spreadsheet

For the supply constraints, the total amount shipped from each source is calculated in column H of the solution table

The supply at each source is included in column J

the cells in column H must equal the corresponding cells in column J

Functional constraints -2Functional constraints -2

The total amount shipped to each destination is calculated in row 18 of the spreadsheet

The demand at each destination is then included in row 20

The total cost is calculated in cell H18 This cost is the sum of the products of the

corresponding cells in the main bodies of the parameter table and the solution table

Solver dialogue Solver dialogue

Excel File All shipment quantities must be

nonnegative Transportation problem is a linear

programming problem The Solver simply uses the general simplex

method to solve a transportation problem rather than a streamlined version

Do not quite fit the model for a Do not quite fit the model for a transportation problem transportation problem

Violate the requirements assumption It is possible to reformulate such a problem to fit

this model buy introducing a dummy destination or a dummy source

When using the Excel Solver, it is not necessary to do the reformulation since the simplex method can solve the original model there the supply constraints are in form or the demand constraints are in form