# Computing the average turnaround time using the multilevel queues

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In a computing center there are four types of jobs according to their

arrival times (in seconds), their priorities and their run times (in seconds);

see the table below:

-----------------Type 1------ Type 2---- Type 3---- Type 4

arrival time---  40  ----------   50 --------  40---------  0

priority---------- 1  ----------    1----------   0----------   0

run time------   1   ------------  2---------   1----------   2

There are 20 Type 1 jobs, 40 Type 2 jobs, 60 Type 3 jobs and 80

Type 4 jobs. Compute the average turnaround time using the multilevel

queues (round robin on every priority level — the higher the

priority, the sooner they run) scheduling algorithm.

[please use a quantum that provides short response time.]

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