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#9 - Global, Cannot Be True, List

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Complete Question Explanation
(The complete setup for this game can be found here: viewtopic.php?t=5761)

The correct answer choice is (B)

The incorrect answers in this question list researchers who could learn both language in a valid solution to the game. The correct answer lists a researcher or researchers who cannot learn both languages in any solution to the game.

In a question requiring a complete list of researchers who cannot learn both Swahili and Yoruba, the first researcher to check is G, because G cannot learn Yoruba. Unfortunately, G does not appear in any answer choice. The next step is to consider the implications of learning both Swahili and Yoruba. Since H, L, and P each learn Yoruba, it seems likely that any combination of two of those three researchers could learn Swahili. Since answer choices (C), (D), and (E) each list two of H, L, or P, it seems unlikely that any of those answer choices are correct. Thus, let us focus on answer choices (A) and (B). Answer choice (A) lists just H, but under the following hypothetical H can be the only researcher who learns both Swahili and Yoruba:


pt28_j99_g2_q9a.png
pt28_j99_g2_q9a.png (1.13 KiB) Viewed 64 times


Let us check answer choice (B):


pt28_j99_g2_q9b.png
pt28_j99_g2_q9b.png (959 Bytes) Viewed 64 times


In this instance the second researcher who learns Swahili cannot be H or L since neither is listed in the answer choice. G also cannot learn Swahili since there is no room for H. Thus P cannot be the only person who learns both Swahili and Yoruba and answer choice (B) is correct.

With answer choice (B), when P is the sole researcher learning both Swahili and Yoruba, a problem arises because a second researcher is needed to learn Swahili, but according to the conditions of the question it must be one who does not also learn Yoruba. In this situation, who could you choose? You cannot choose L or H because they already learn Yoruba. That leaves only G, but if you select G for the second researcher slot in Swahili, you immediately violate the last rule because there is no room for H (and H could not be chosen anyway because that would be a violation as H learns Yoruba already). Hence, answer choice (B) cannot be a complete and accurate list of researchers who learn both Swahili and Yoruba.

When you are trying to figure out a situation such as the one above, always remember to try to work out the solution by creating hypotheticals. In this instance you can create viable hypotheticals for (A), (C), (D), and (E), but you cannot create one for (B).
eober
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What is the reason why palaeontologist cannot learn both S and Y? The only researcher I thought would not be able to learn both S and Y was the geologist.

I inferred that exactly 3 researchers who learn Y would have to be P, H and L. Because if G was there then H would also be there but G cannot be with L or P.

Also G and H can be together only if they are placed to S or T, but they cannot be present together in any other language.

Could you provide explanation to where I am going wrong?
Nikki Siclunov
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Hi eober,

You made the correct inferences in your initial setup, but misinterpreted the question stem. The question states, "each of the following could be a complete and accurate list of the researchers who learn both S and Y, EXCEPT..." The correct answer choice will contain either an incomplete, or an inaccurate, list of researchers who learn both S and Y.

Of course, the paleontologist can learn both S and Y - there is no problem with that. The problem with answer choice (B) is not that it's inaccurate, but rather that it's incomplete! The paleontologist cannot be the only scientist who learns both S and Y, because there are two researchers who must learn S. If the paleontologist is one of the two, then the other one cannot be the geologist (fifth rule), and so he must be either the linguist or the historian. Both of them, however, must learn Y. Thus, the paleontologist cannot constitute the complete list of researchers who learn both S and Y.

Does this make sense? Let me know.

Thanks!
Nikki Siclunov
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jgray
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in the set-up for this game, pg 245 LGB 2013, can you explain the 3>R>1?
Dave Killoran
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Hi J,

It refers to the reference in the game scenario that each researcher "will learn at least one and at most three of four languages." It could be represented alternately as "Res :arrow: 1, 2, 3" or something similar.

Please let me know if that helps. Thanks!
Dave Killoran
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Sherry001
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Hello !
Could someone please help me understand question 9 for this game? I spent so much time and still cannot figure out the difference between A and B.


I just see A and B as both incomplete ! For A) if the historian learns S And Y we still have another S to distribute and it could go to any of the researchers unless they learning R as well!
The only way I see A being correct is if The geologist learns two languages . But this is a could be true .. So I'm lost .



Thanks so much
Sherry
Adam Tyson
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Hey Sherry, let me see if I can help. First things first here - the question is not a Could Be True question but rather a Cannot Be True, in that it says that each of the following could be true EXCEPT. So, which of these answer does NOT work? In other words, which answer cannot be the complete list of everything Groups S and Y have in common?

Start by looking at the numerical distribution in the game, which they are kind enough to spell out for you with the first 4 rules. Group R has just 1 variable, Groups S and T have two each, and Group Y has three.

Next, since neither P nor L can be in the same group as G, we can infer that G is NOT among the variables in Group Y. That group has to be H, L and P.

Also, while it doesn't end up impacting this particular question, G cannot be in Group R either, because the last rule requires that anywhere G goes, H must also go.

Now, think about each answer in q9 and, in the cases of answers A and B ask yourself "what could the other variable in Group S be?" It can't be anything else that appears in Group Y, because then we wouldn't have a complete list of the variables that those two groups have in common.

For answer A, the other variable in Group S could be G. That is, Group S could have H and G in it while Group Y has HLP in it, and the only variable in both is H. Answer A therefore could be true, and is therefore a wrong answer.

What about answer B now? If P is in Group S, what could you pair it with? Not G - that violates one of the rules. If we tried to pair it with H or L, then P would NOT be the only variable that is in both S and Y. That's why B is the correct answer.

Hope that cleared things up!
Adam M. Tyson
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Peter8123
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Adam,

I'm sorry for bringing up an old and possibly already answered post, but even after reading all of the replies on this page, as well as others, I still have not come across the specific problem I am finding with the answer of B for question 9, and the reasoning behind this answer.

I am using the LG Bible 2016 Edition. On page 355, the explanation states that:

"Since H, L, and P each learn Yoruba, it seems likely that any combination of the two of those three researchers could learn Swahili. Since answer choices (C), (D), and (E) each list two of H, L, or P, it seems unlikely that any of those answer choices are correct. Thus, let us focus on answer choices (A) and (B)." This is apparently all of the information required to exclude answer choices (C), (D), and (E), as no mention of these answer choices are made after the above quote.

Continuing the explanation, on page 356, in regards to answer choices (A) and (B), they state:

"In this instance the second researcher who learns Swahili cannot be H or L since neither is listed in the answer choice... Thus P cannot be the only person who learns both Swahili and Yoruba and answer choice (B) is correct."

I agree that any two combination of H, L, and P could learn Swahili. What I do not agree with is that any two combination of H, L, and P could also learn Yoruba, as Yoruba requires THREE researchers. Therefore, every single answer choice (A) through (D) has researchers not "listed in the answer choice," as the quote on page 356 states is enough to disqualify answer choice (A).

The way I currently see it, none of the answer choices are complete. Any help would be greatly appreciated.
Adam Tyson
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Happy to help, Peter! The list we are looking at in this answer choice is a complete and accurate list of the researchers that could be in both of those groups, S and Y, in any one particular scenario. You can never have all three in group S, which is limited to two researchers.

H and L COULD be the complete and accurate list of the researchers that the two groups have in common, if H and L were the two researchers that learn S. Same thing for H and P, and for P and L. H can be the only one in common if H and G are the ones to learn S.

P, however, cannot be the complete list of researchers the two have in common, because group S would have to also include either H or L, such that both P and the other one would be in groups S and Y.

They key here is that we are looking at a single solution, not all the various combinations that could exist. That should do the trick for you, I expect! The language "could be a complete and accurate list" indicates "in a given solution"; if instead it said "is a complete and accurate list of all the researchers that could" be in both groups, then you would need all three of H, L, and P. Crucial difference, "is...all" vs "could be". Watch out for that!
Adam M. Tyson
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Peter8123
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Adam,

Thank you for clearing that up. It makes complete sense now.

Best,

Peter
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