We claimed in the Repco model that we could either constrain the units produced to be greater than or equal to the units used by production or the units sold to be nonnegative. We chose the former....

We claimed in the Repco model that we could either constrain the units produced to be greater than or equal to the units used by production or the units sold to be nonnegative. We chose the former. Modify the model to implement the latter (deleting the former), and verify that you get the same optimal solution.