Which one of the following could be a matching of the students to the subjects on which they present?

R on July 15, 2018

Game Explanation

Hi there, can I please get an explanation for the setup for this game?

1 Reply

Christopher on July 28 at 05:43PM

@RJEh, this is a grouping game, so the first thing to do is to identify what your groups will be. In this case, since you can have multiple students present on each of three lectures, your groups are M, J, S. Before getting into the rules, you know that there must be at least one presentation on each subject, and there's no limit to the number of presentations, so it is theoretically possible (before getting into the rules) that all three students present on all three subjects. I'd start with this as the diagram and go from there into the rules.

_ _ _ _ _ _ _ _ _
M J S

Then getting into the rules:

Rule one diagrams as GJ -> RJ and not RJ -> not GJ. This rule doesn't do much to the diagram. It is still possible for J to only have one presentation from W, but it could also have two from R and G or three from R, G, and W.

Rule two diagrams as RS -> not WS and WS -> not RS. This rule means that S can have a max of 2 presentations.

Rule three diagrams as M -> S and not S -> not M. This rule piggy-backs on rule two and means M can only have a max of 2 presentations.

So the diagram is narrowed to:
_ _ _ _ _ _ _
M J S

As you start going into the questions, if you see any that have more than two presentations on M or S, you can immediately rule them out (for instance, (B) on the first question). Otherwise, you'll have to run hypotheticals through each rule.

Does that help?