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|                      |     Transportation Cost |                                   |
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|  Plants    |      site-1     |     site-2   |        Available Supply              |
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|  Plant-1   |        5        |       2      |            90                        |
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|  Plant-2   |        4        |       3      |            160                       |
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|  Demand    |       100       |      60      |                                      |
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Hint: Formulate this problem as we have exaplained in the previous example.

# The optimal value should be 520.

# The optimal solution should have x12=60, x21=120 and all others have zero.