A variation of the round robin scheduling algorithm is a preemptive round robin. Each process is assigned a numerical priority, with a higher number indicating a higher relative priority. In addition to the processes listed there is an idle process with a priority of zero that is only scheduled where no other processes are available. The time quantum is 10 units of time. If a higher priority process arrives in the system, it preempts a lower priority process that is executing. A preempted process is returned to the end of the ready queue. Process/ Priority Burst Duration Arrival time P1 40 30 0 P2 30 15 25 P3 30 20 30 P4 35 24 60 P5 5 31 100 P6 10 18 105