We see that the total cycle time is equal to 6.20 hrs and the resulting total cost is $1,060. Both of these numbers are better than the previously considered configuration of using three machines of option 2 for the station 1. Hence, we decide to stick with this configuration.
We note that the procedure described above is based on trial and error and it will not necessarily lead to an optimal solution, unless we perform an exhaustive search over all possible configurations. This is a typical use of queueing theory as a “design” tool; i.e., queueing theory essentially allows the systematic evaluation of the performance resulting from each considered alternative.
In the more specific context of our example, it is unclear without any further analysis and/or computation whether the generated solution is optimal; all we can say is that it is a configuration that meets the posed production requirements at a fairly low cost.