FCFS average waiting time
The situation
Four processes arrive at a single CPU:
| Process | Arrival | Burst | |---------|---------|-------| | P1 | 0 | 8 | | P2 | 1 | 4 | | P3 | 2 | 9 | | P4 | 3 | 5 |
Waiting time = turnaround time − burst time. Turnaround time = completion time − arrival time.
Under first-come first-served, what is the average waiting time?