Using Johnson’s rule, find the optimal sequence.

Question

Consider the following jobs and their processing times at corresponding machines:-

Job	Duration (Hours)
	m/c 1	m/c 2	m/c 3
	t1	t2	t3
A	13	5	9
B	5	3	7
C	6	4	5
D	7	2	6

      Using Johnson’s rule, find the optimal sequence.