Diagram

[noah]

Here's the diagram I used. I came up with 2 frames based around which day 4 & 7 were assigned to. Tell me if you have any questions on these.

[nazu.s.shaikh]

With this game, I had a bit of uncertainty with Q6, I was only able to cancel out E because of the last constraint where 6 7 4 would be paid on opposite days because if 6 (Wed) then 7&4 (R) and if 6(R) then 7&4 (Wed).

My method really was go through each scenario however when diagramming out the answer choices how would I know whether I should put the extra slot for a bill on Wednesday or Thursday?

For example :

Answer choice A:

Wed. R
3 2
1/5 1/5
4 6
7

or

Wed. R.
3 2
1/5 4
6 7
1/5

How do I know that this "could" be true instead of saying "this must be true" because from the looks of it it worked out well against the constraints... basically what is stopping me from saying " this must be true" if all the constraints are working in this?

[noah]

Good question. I see a few problems in your approach. First of all, take a look at the diagram I posted above - there aren't that many possible scenarios, and it's possible to "frame" the game rather easily. If you use that diagram, #6 (and the rest of the questions) fall down pretty quickly.

But, it's important to look at your approach. If you don't end up with some cool diagram that more or less breaks the game into easy bite-sized pieces - which definitely does not happen all the time - you are left using other tools. #6 is an unconditional question, so there's no new rule to use to follow an inference chain. So, instead you have to rely on your general understanding of the game. Ideally, you "get" the game enough that you can eliminate some of the answer choices without spelling them out. But, you may end up doing trial and error (and, if you do find yourself doing that on a game, know that you can probably figure out a way to avoid that - it's worth exploring what that would entail when you review the game later).

If you're going to do trial and error, it's important to make the most of it. First of all, with a must be true answer, the 4 incorrect answers are could be trues - or perhaps a can't be true, but that's unlikely. Your goal when looking at an answer choice in this situation - a must be true question - is to "break it." Can you come up with a scenario in which the answer choice doesn't have to be the case? For (A), you tried to prove it could work, when you should be looking to see if there's a situation where it doesn't hold true. So, you could have come up with:

W R
/ 1/5
1/5 2
7 3
4 6

This shows that (A) does not have to be true.

Finally, you are making an inference about the 4/7 & 6 rule combination that seems based on a slight misunderstanding. It is true that 7/4 and 6 have to be on opposite days, but it's not because we can simply go:

6w --> 7 & 4 R
thus 7 & 4 w --> 6r. This inference is true, but it leaves the possibility that 7,4 and 6 are all on Thursday. That's not possible because of space. I just want to make sure you're not jumping to that inference for the wrong reason.

If you want to play around with the idea of how to "break" must be true answers, go ahead and come up with a counter-scenario for each of the other answer choices. You could also try this for #4.

I'll be happy to look at those if you post them.

Does that answer your question?

[nazu.s.shaikh]

Finally, you are making an inference about the 4/7 & 6 rule combination that seems based on a slight misunderstanding. It is true that 7/4 and 6 have to be on opposite days, but it's not because we can simply go:

6w --> 7 & 4 R
thus 7 & 4 w --> 6r. This inference is true, but it leaves the possibility that 7,4 and 6 are all on Thursday. That's not possible because of space. I just want to make sure you're not jumping to that inference for the wrong reason.

Sorry I should have clarified myself better. What I inferred from the 6, 7&4 rule was the following;

6 7 4 cannot happen all on Wednesday, this we know for sure.

6 7 4 cannot happen on Thursday because then it would push 1/5 together on Wednesday which we cannot have.

Is that something along the lines of what you were saying?



So with taking your advice, I was able to cancel out D as well because in Q4 it had to be true that if B6 was paid on Wed than B3 had to also have been paid on Wednesday so it doesn't have to be true that if B6 is paid on R then B3 is also paid on R. Either day could work.

3 down. 2 to go.

For B I diagrammed it as follows:

Wednesday : 5 3 6
Thursday: 4 7 1 2

Either way could be true for answer choice B.

C was the only one where having put 4 & 3 together on the same day did not work. B4 and B3 had to be put on opposite days

Wednesday: 1 5 6
Thursday: 4 3 2 7

Wednesday: 4 3 7
Thursday: 1 2 5 6

Therefore B4 and B3 would have to be paid on opposite days.

Wednesday:

[noah]

Looks like you're getting the hang of it. Along with working on how to eliminate must be true answers, you should work on developing full diagrams for games - framing is a big and important issue. I don't know if you're an Atlas student, but if so, you should watch session 4 on advanced ordering and then watch the advanced framing lab - it goes into framing in detail.

Good luck!

[megm7267]

Hi Noah - Could you please explain how you set up this diagram? Is it closed assignment/3D Ordering?

I'm really confused as to how to set the problem up..shouldn't there be three days listed?

Thanks

[ManhattanPrepLSAT1]

Hi megm7267!

If you don't mind, I'll offer up answers to your questions. This is actually neither 3D Ordering nor Closed Assignment. This is actually an Open Binary Grouping game. Crazy, huh?

We know that either 3 or 4 of the bills are paid on Wednesday, the rest on Thursday. So no need to worry about any bills potentially going on Tuesday.

We can use numerical distributions to establish that either 3 bills are paid on Wednesday (and 4 on Thursday) or that 4 bills are paid on Wednesday (and 3 on Thursday).

Start by separating bills 1 and 5. Use 1/5 ----- 5/1 notation as place holders, and then see where you can fit the chunk of bills 4 and 7. If you need more help beyond that, let me know! But I'd bet you could take it from there...

[noah]

Here's the diagram I used. I came up with 2 frames based around which day 4 & 7 were assigned to. Tell me if you have any questions on these.

And here's a more traditional diagram:

PT29, S3, G2 – Seven Bills - Manhattan LSAT.pdf

(63.45 KiB) Downloaded 441 times

Probably most students will find this to be what they came up with - and it works well.