Use transportation model to develop a minimum cost production schedule for the products and machines. Then use LINDO$/$LINGO to solve it and find the optimal solution.

The optimal units of product A on machine $1$ is:

The optimal units of product A on machine $2$ is:

The optimal units of product A on machine $3$ is:

The optimal units of product B on machine $1$ is:

The optimal units of product B on machine $2$ is:

The optimal units of product B on machine $3$ is:

The optimal units of product C on machine $1$ is:

The optimal units of product C on machine $2$ is:

The optimal total cost is: $($Don$\text{'}$t write the $ sign in your answer! Write your answer as integers. For example, $500)$