PMI-SP Exam - Topic 1 Question 39 Discussion

Fred should add lag time to each painting activity. Since lag time is waiting time, Fred

will have to wait twenty-four hours after the priming is

finished before he can start painting.

What is a lag?

A lag directs a delay in the successor activity. Lags require the dependent activity to have added

either to the start date or

to the finish date of the activity. For example, in a project of making radio-controlled airplanes, after

applying glue and

pasting stickers, it requires twenty-four hours to dry the glue. Any activity can be started after that

only. This period, of

twenty-four hours, is a lag.

Answer option C is incorrect. There is no reason to add an intermediary task as waiting. Adding lag

time is the most appropriate as there are

fewer activities to manage.

Answer option D is incorrect. Priming all of the room first and then painting all of the rooms would

cause Fred to readjust the entire

sequencing of activities. In addition, we do not know the reason why Fred has scheduled all the

rooms to be primed and then painted. There

may be successor activities in the project that need to enter each room, such as carpeting, as soon

as a room has been painted. If that were

the case the additional activities would have to wait for all of the priming to be completed and then

the sequential rooms to be painted before

they could start.

Answer option A is incorrect. Lead time actually moves activities closer together rather than farther

apart. Lead time would cause the painting

and priming activities to overlap, something that Fred does not want to happen.

What is a lead?

A lead allows an acceleration of the successor activity. It works just the opposite of lag. For example,

in a software

application project, before designing is fully completed for first phase, a program development

group can start this phase

programming. This overlapping of timing is a lead.