RR - Round Robin. Assume the quantum is 3. The Gantt chart can also be used to find the finish times for this preemptive scheduling algorithm.

Gantt Chart:

        +------------------------------------------+
        |  P1    |  P2  |  P3  | P1* |  P2*  | P3* |
        +------------------------------------------+
        0        3      6      9    10      13    14

        Time     0  1  2  3 
        READY    P1 P2 P2 P2  ...
        P3 P3
        P1
     

From the Gantt chart, finish times are:

Process	Finish	Wait
P1	10	6
P2	13	6
P3	14	8

So, for example, the wait time for P3 is:

        Wait = Finish - Arrival - CPU_Burst = 14 - 2 - 4 = 8
     

and the average wait time for these three:

        Avg. Wait = (6 + 6 + 8)/3 = 6.667