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Hello folks,

So my main issue has been with logic games, and grouping games in particular. Would in/out games be considered a subset of grouping games? For an example of a game that I had somewhat of an issue diagramming, December 2001 had a fruit stand with fruits that can be in or out depending on what other fruits are on the stand. I'll list the game here:

A fruit stand carries at least one kind of the following kinds of fruit: figs, kiwis, oranges, pears, tangerines, and watermelons. The stand does not carry any other kind of fruit. The selection of fruits is consistent with the following conditions:
If the stand carries kiwis, then it does not carry pears.
If the stand does not carry tangerines, then it carries kiwis.
If the stand carries oranges, then it carries both pears and watermelons.
If the stand carries watermelons, then it carries figs or tangerines or both.

How would you go about tackling this problem? Writing out the conditionals and then the contrapositves might be a good step, and I tried. Should I set up an In/Out box? Is this an in/out game?

Edit: I figured perhaps I should put down the couple problems I got wrong to see how people would go about solving them.

4. If the stand carries no watermelons, then which one of the following must be true?
A. The stand carries kiwis.
B. The stand carries at least two kinds of fruit.
C. The stand carries at most three kinds of fruit.
D. The stand carries neither oranges nor pears.
E. The stand carries neither oranges nor kiwis.

5. If the stand carries watermelons, then which one of the following must be false?
A. The stand does not carry figs.
B. The stand does not carry tangerines.
C. The stand does not carry pears.
D. The stand carries pears but not oranges.
E. The stand carries pears but not tangerines.

For some reason it's the first two rules that are throwing me for a loop, even though I can't pinpoint exactly why. Perhaps I'm overthinking it.

Thanks for the help...

Not sure if you know our method of diagramming these games, but take a look. I'm afraid I don't have the ability to load an image onto a server right now, so you'll have to find it here: http://www.manhattanlsat.com/forums/pre ... 5042b9699a

Yes, in/out games are absolutely grouping games, with the groups being "In" and "Out".

So what you want to do is exactly what you said - draw a chart with the two groups and then list out the conditionals and contrapositives.

#4: If no watermelon, then no orange, by clue 3. That's all we know, so to the answer choices we go.
A) Don't know this to be true. Move on to the next answer choice.
B) Don't know this to be true. Move on to the next answer choice.
C) Hmmm. Let's test this one. We know two fruits are out, so question that needs to be answered here is whether all the other fruits (F,K,P,T) could all be in. If they can't all be in, then this is the correct answer. Sure enough, by Clue 1, K and P cannot be in together, so this is our answer.

#5: If watermelon, then either F or T (or both) must be in. So draw out two hypotheticals. Hypo 1: WF in. Hypo 2: WT in. Those conditions bring no new information. Since that's all we know, to the answer choices we go.

A) Don't know this to be false. Move on to the next answer choice.
B) Don't know this to be false. Move on to the next answer choice.
C) Don't know this to be false. Move on to the next answer choice.
D) Let's test whether this could be true (if it could be true, it's not our answer). Hypo 1: WFP in, OK out. No problem there. Hypo 2: WTP in, OK out. No problem there. Looks like it could be true.
E) Let's test whether this could be true. Hypo 1: WFP in, T out. VIOLATION. If T's out, K is supposed to be in. But if P's in, K's supposed to be out. This is our answer. (Hypo 2 need be tested as WT in already makes this answer choice false.)

Conditional games are important to understand, as they appear frequently. Good luck!

Thanks so much for the helpful replies!

I didn't really have much of a problem setting up the conditionals, I just wasn't sure how exactly those fit in the diagram, whether or not those were supposed to go in the in/out charts or not. To be honest I may be overthinking it slightly, if I can get as far as the conditionals then I should just be able to solve it based on that.