Question

Find the sequence that minimizes the total elapsed time to complete the following jobs in the order AB. Find the total elapsed time and idle times for both the machines.

Job	I	II	III	IV	V	VI	VII
Machine A	7	16	19	10	14	15	5
Machine B	12	14	14	10	16	5	7

Solution:

Using the optimal sequence algorithm, the following optimal sequence can be obtained.

`square`

`square`

IV

V

III

`square`

`square`

Total elapsed time is obtained as follows

Job	Machine A		Machine B
	Time In	Time  Out	Time In	Time Out
`square`	0	5	5	12
`square`	5	12	12	24
IV	12	22	24	34
V	22	36	36	52
III	36	55	55	69
`square`	55	71	71	85
`square`	71	86	86	91

∴ Total elapsed time T = 91 units

Idle time for machine A = `square` units

Idle time for machine B = `square` units

Answer 1

Using the optimal sequence algorithm, the following optimal sequence can be obtained.

\[\boxed{VII}\]

\[\boxed{I}\]

IV

V

III

\[\boxed{II}\]

\[\boxed{VI}\]

Total elapsed time is obtained as follows

Job	Machine A		Machine B
	Time In	Time  Out	Time In	Time Out
\[\boxed{VII}\]	0	5	5	12
\[\boxed{I}\]	5	12	12	24
IV	12	22	24	34
V	22	36	36	52
III	36	55	55	69
\[\boxed{II}\]	55	71	71	85
\[\boxed{VI}\]	71	86	86	91

∴ Total elapsed time T = 91 units

Idle time for machine A = \[\boxed{5}\] units

Idle time for machine B = \[\boxed{13}\] units