Patient	Cut time (hrs)	Sew time (hrs)	Start cut	End cut	Start sew	End sew
A	2.3	2.8	0.0	2.3	2.3	5.1
B	2.5	3.0	2.3	4.8	5.1
C	2.0	1.5
D	0.6	1.0
E	3.6	2.6

Johnsons Rule for two tasks

The goal of Johnsons Rule is to reduce the total Makespan. Here are the rules:

Find the task (cut time or sew time) that is the smallest. In this case, it is Patient D (0.6 cut time). Now you must decide when to schedule the task. If the task is associated with the first process (cut time), put the item at the top of the list. If the task is associated with the second process (sew time), put the task at the bottom of the list. In our case, 0.6 is the cut time (first item) so it is scheduled first.

Patient	Cut time (hrs)	Sew time (hrs)	Start cut	End cut	Start sew	End sew
D	0.6	1.0

Now, it is time to schedule the second task. Task C has a sew time of 1.5 hrs, so it should be scheduled next. Sew time is the second task, so Task C should be scheduled last.

Patient	Cut time (hrs)	Sew time (hrs)	Start cut	End cut	Start sew	End sew
D	0.6	1.0
C	2.0	1.5

The third lowest value is Patient A who has a cut time of 2.3 hrs. This is the first task so we will schedule Patient A at the top level that is still available.

Patient	Cut time (hrs)	Sew time (hrs)	Start cut	End cut	Start sew	End sew
D	0.6	1.0
A	2.3	2.8
C	2.0	1.5

Complete the assignment of the two other Patients and then calculate the Makespan.

What is the total Makespan for these five jobs? ___________

What is the decrease in Makespan using Johnsons Rule? ____________________

What is the change in productivity using Johnsons Rule? ____________________

What is the change in efficiency for Doctor 2 using Johnsons Rule? ____________________