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#71220
This game is discussed in our Podcast: LSAT Podcast Episode 31: The September 2019 LSAT Logic Games Section

Complete Question Explanation
(The complete setup for this game can be found here: https://forum.powerscore.com/lsat/viewtopic.php?t=31312)

The correct answer choice is (E).

This is an interesting question, and one that at first can appear to be standard Rule Substitution question. But instead, the test makers return to a question type that appeared more frequently in the past, and one that has largely been replaced by Rule Substitution questions in recent years.

First, in standard Rule Substitution questions, the test makers identify a rule and then ask you to find the answer choice that would have the exact same effect as the rule in question. You are effectively asked to find a substitute that has identical results. With that in mind, let's look at this question stem and examine the differences:

Here the test makers tell you that one of the rules (#5) is first suspended and then replaced with an entirely new rule (this time it is similar to #5 but with a key twist). Then, you are asked to find what must be true now that the change has been made. So, instead of finding a new substitute rule, you are given that rule and then have to make a new setup to determine the implications.

Note: This is one of the worst types of questions to encounter because it requires re-assessing your entire setup! You now have to look at everything you did as a result of rule #5 and change it. Typically, it's as if you've got an entirely different game (yes, there is overlap, but some key information has changed so our inferences change; that requires a reboot of a large portion of the work that was done). Because this takes so much time, if you are struggling with time in Logic Games then this is a question type you should skip!


Answer choice (A):

Answer choice (B):

Answer choice (C):

Answer choice (D):

Answer choice (E): This is the correct answer choice. Someone in addition to Z has to have an HR combo as their two "single" flowers, so let's look at the options to see who that could be.

  • It cannot be S, because per the original rules that are still in effect, S has to have TWO Rs.

    It could be T! Under the original rules, T has exactly one H and at least one G. We originally inferred that T could not have any Rs, because S is the only one allowed to have two of them and Z was the only one allowed to have just one H and just one R. But now that rule has been replaced, and T could possibly have one H, one R, and two Gs. If that happens, then T has no Ls.

    It could also be U! The original rules required U to have an H and an R, and under this new rule U could then have either two Gs or else two Ls. We'll come back to what that means for the rest of the setup in a minute.

    It could be W! We originally inferred that W had to have an L with his two Gs, but now W could have an H and an R, and no Ls.

    Z remains unchanged in this case, and so has either two Ls or else two Gs.
Now let's look and see what happens if U is the only one other than Z to have exactly one H and exactly one R. This is where the last rule is really going to matter, because only one person has two Ls. If that person is U, then U has HRLL. Now look at what that does to Z - Z would have to have HRGG, because they cannot both have two Ls! And if Z has two Ls, then U would have to have two Gs instead, and again we have at least one person with no Ls. There's just no way to work it out that two people have an H and an R and two Ls.

When you think about it, if we look at this question only in terms of the impact of that last rule, we don't even have to worry about who the other person is that has one H and one R. That's actually a trap to make us waste time! If two people - ANY two people - have one H and one R, then they each have to have either two Gs or two Ls to finish their arrangement. Since only one person can have two Ls, the other has to have two Gs and therefore has no Ls.


This explanation is still in progress. Please post any questions below!
 tlaurenceline
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#72354
Why must it be true that at least one arrangement contains no Lillies ?
 Adam Tyson
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#72364
In this Suspension question, tlaurenceline, someone in addition to Z has to have an HR combo as their two "single" flowers. Let's look at the options to see who that could be!

It cannot be S, because per the original rules that are still in effect, S has to have TWO Rs.

It could be T! Under the original rules, T has exactly one H and at least one G. We originally inferred that T could not have any Rs, because S is the only one allowed to have two of them and Z was the only one allowed to have just one H and just one R. But now that rule has been replaced, and T could possibly have one H, one R, and two Gs. If that happens, then T has no Ls.

It could also be U! The original rules required U to have an H and an R, and under this new rule U could then have either two Gs or else two Ls. We'll come back to what that means for the rest of the setup in a minute.

It could be W! We originally inferred that W had to have an L with his two Gs, but now W could have an H and an R, and no Ls.

Z remains unchanged in this case, and so has either two Ls or else two Gs.

Now let's look and see what happens if U is the only one other than Z to have exactly one H and exactly one R. This is where the last rule is really going to matter, because only one person has two Ls. If that person is U, then U has HRLL. Now look at what that does to Z - Z would have to have HRGG, because they cannot both have two Ls! And if Z has two Ls, then U would have to have two Gs instead, and again we have at least one person with no Ls. There's just no way to work it out that two people have an H and an R and two Ls.

When you think about it, if we look at this question only in terms of the impact of that last rule, we don't even have to worry about who the other person is that has one H and one R. That's actually a trap to make us waste time! If two people - ANY two people - have one H and one R, then they each have to have either two Gs or two Ls to finish their arrangement. Since only one person can have two Ls, the other has to have two Gs and therefore has no Ls. Boom, done!
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 NegusAlfie
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#87633
If Z has double Ls, why can't U have: HRGL?
 Robert Carroll
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#87659
Negus,

It's still not possible for anyone to have all four kinds of flowers, as the constraint of the scenario is still in play: "Each person uses exactly three kinds of flowers."

Robert Carroll
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 Chantal
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#93308
What's the most efficient way of solving this question? I did it by Process of Elimination, but that ended up taking a lot of time.

What I did was draw a new game board (taking the new rule into account) and eyeball the answer choices one by one. So for (A), I looked at my game board and thought: "Eh, Ursula could be the other person with 1R and 1H, Tabitha doesn't need a rose." For (B), I looked at my game board and figured that everyone could have roses, so on and so forth. (E) was the only one I actually drew out two new game boards for, just to make sure I didn't miss anything in the previous ACs. But that took nearly 2 minutes, which seems way too long to spend on a question. Is there a faster way of solving this question that I missed?

Thanks in advance!
 Rachael Wilkenfeld
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#93317
Hi Chantal,

Honestly, I find the rule substitution questions to be among the most time consuming questions in LG. For that reason, when they show up on a test, I frequently punt them until the end of the test. They are worth the exact same number of points as a less time consuming question. Plus since these often require a bit of a new diagram (as you found) or at least a major diagram change, it doesn't hurt that much to come back at the end.

Anyway, the way I did this one was to draw out the new scenario briefly, and eliminate any answer choices that I could quickly by using a counter example. I'll take you through my thought process more below.

Answer choice (A): T can have two roses, or zero roses (for example ghrr for T, and the other rh being W). That was a fairly quick elimination.

Answer choice (B): I can make it so that everyone has at least one rose. Quick elimination.

Answer choice (C): Z and any/all of T, W, and U could have hr, so we know we aren't limited to two.

Answer choice (D): We know t, U and Z all have h. W could have rh. S could have h as well. Another elimination.

Answer choice (E): This is our correct answer. On first glance, I can't eliminate it, so I personally drew this one out. I drew L's across the 4th slot of all my people. Once I did that, I could see that I wouldn't have space to do another RH (in addition to Z) without also doing an extra LL potentially. Oops. Here's the one that must be true.

As I said above, this would be the one I would skip until the end on test day. Mostly because I don't know going into the question how many of these answer choices I'd need to draw out.

Hope that helps!

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