Question: Barbara and Jenny's Ice Cream Company produces four different flavors of ice cream: vanilla, chocolate, strawberry, and peanut fudge. Each batch of ice cream is produced in the same large vat, which must be cleaned prior to switching flavors. One day is required for the cleaning process. At the current time they have the following outstanding orders of ice cream:
It takes one day to produce the ice cream and a maximum of 100 gallons can be produced at one time. Cleaning is required only when flavors are switched. The production for one flavor will be completed prior to beginning production for another flavor. Cleaning is always started at the beginning of a day. Treating each ice cream flavor as a different job, find the following:
a. The sequence in which the ice cream flavors should be produced in order to minimize the mean flow time for all of the flavors.
b. The optimal sequence to produce the flavors in order to minimize the number of flavors that are late.