The Door Knob Company has four orders on hand, and each must be processed in the sequential order:

First: Department A—press shop Second: Department B—plating and finishing The following table lists the number of days required for each job in each department. For example, job IV requires one day in the press shop and one day in the finishing department.
Assume that no other work is being done by the departments and that “no passing’’ of jobs is allowed. Use a Gantt chart to show the best-work schedule. (Best-work schedule means minimum time to finish all four jobs.)
Job I Job II Job III Job IV Department A 8 8 5 1 Department B 8 3 4 1