Given the following processes with their times and priority (lower number indicates higher priority)

Process	Burst Time	Priority
P1	10	3
P2	1	1
P3	2	4
P4	1	5
P5	8	2

Which of the following is a value of average waiting time using priority scheduling algorithm?

Concept:

In Priority Scheduling (Non-Preemptive), the process with the highest priority (i.e., lowest numerical value) is scheduled first. If two processes have the same priority, FCFS (First-Come-First-Serve) is used.

FORMULAE:

TAT = CT − AT

WT = TAT − BT

AT (Arrival Time) is assumed to be 0 for all processes in this question.

Analysis:

GANTT CHART: P₂ → P₅ → P₁ → P₃ → P₄

Average Waiting Time =\(\frac{0 + 1 + 9 + 19 + 21}{5} = \frac{50}{5} = 10.0​​​​\)

Hence, the correct answer is: option 4.  The accurate average waiting time is 10.0 units.