Precedence Tables (SQA National 5 Applications of Mathematics): Flashcards

A precedence table sets out every activity in a project, one to a row, together with what has to be finished before each one can begin.

It is the starting point both for drawing an activity network and for working out how long the project must take.

The completed sentence is:

Each row is one activity, labelled by a letter, and the columns give a short description, the preceding activities that must come first, and the time that the activity takes.

The time can be in any unit, so read the column heading before adding anything up.

It is the activity with no preceding activities listed against it.

You find it by looking down the preceding-activity column for the row that is empty, and it goes on the far left of the network.

True.

An activity listed as preceded by C and I cannot begin until both of them are finished.

This is what makes two separate routes through the network merge at that activity.

It is the activity that never appears in anyone else's list of preceding activities.

This needs a different search from finding the start: instead of looking for an empty row, you scan the whole preceding-activity column for a letter that is missing from it.

Begin at the starting activity, then look for an activity that lists it as a preceding activity.

Carry on that way, each time finding an activity preceded by the one you have just reached, until you arrive at the final activity.

Repeat from the start along each different branch until every route has been found.

False.

It is the longest route, because every activity has to be completed and the project is not finished until the slowest chain is done.

The shorter routes simply run alongside it and finish with time to spare.

The route takes 71 minutes.

Adding the activity times straight along the route gives .

Only the activities actually on the route are counted; anything on a different branch belongs to a different total.