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805+ Level|   Resolve Paradox|         
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In the United States, vacationers account for more than half of all vi 19 Feb 2021, 11:25
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Can someone please explain why is option D wrong. I read each one of the explanations, but am still not 100% convinced.

If people who go to the zoo add up twice to the number of people who visit a pure aquarium, the number of people who visit a pure aquarium can go up. Why are we bothered about people who don't visit etc? or that this is a likely scenario? Every option, even option B, is a likely scenario only. No option in this question says that "this" definitely happens.

Experts please help me understand how to eliminate D.
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First, let’s consider the information provided in the passage:

  • Of pure aquarium visitors (PAM), greater than 50% are vacationers.
  • Of zoo visitors (ZV), less than 25% are vacationers.

So, the passage introduces a paradox about the proportion of visitors that vacationers make up. Vacationers are MORE than 50% of pure aquarium visitors. BUT vacationers are LESS than 25% of zoo visitors.

The question asks that we identify an answer choice that helps account for the paradox. In other words, which answer choice explains why vacationers make up a smaller proportion of pure aquarium visitors than of zoo visitors?

Quote:
(D) People who visit a zoo in a given year are two times more likely to visit a pure aquarium that year than are people who do not visit a zoo.
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(D) tells us that people who visit a zoo are more likely to visit a pure aquarium than people who do not visit a zoo. So, if someone who doesn’t visit the zoo has a 10% chance of visiting an aquarium, then someone who visits a zoo has a 20%+ chance of visiting an aquarium. But this would apply to both vacationers and non-vacationers.

We’re not looking to explain why a certain number of people go to the zoo or go to the aquarium. We’re looking to explain why vacationers make up a greater proportion of pure aquarium visitors than zoo visitors. The information provided in (D) applies to both vacationers and non-vacationers, so it does not explain the discrepancy. Eliminate (D).

And here’s (B):

Quote:
(B) Virtually all large metropolitan areas have zoos, whereas only a few large metropolitan areas have pure aquariums.
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(B) is interesting. It indicates that large metropolitan areas have zoos but NOT pure aquariums. So, people living in large metropolitan areas could visit zoos without going on vacation, but they would have to go on vacation to visit pure aquariums. This would explain why a greater proportion of pure aquarium visitors are vacationers. Namely, they MUST go on vacation to get to a pure aquarium.

This speaks to the heart of what we were trying to explain, so (B) is the best answer choice.

I hope that helps!
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In the United States, vacationers account for more than half of all vi 31 May 2022, 10:24
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Hi KarishmaB AndrewN

There is no mention in the question that the vacationers are coming from large metropolitan cities. What if they are coming from a place that has the same number of aquariums and zoos? There is no way we can assume the place where the vacationers are actually coming from and what are the qualities of that place.

Having said that, is B correct just because it helps us provide an answer as to "why" a certain trend is taking place, even if it includes certain information that is well out of scope ?
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In the United States, vacationers account for more than half of all vi 31 May 2022, 13:22
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Namangupta1997
Hi KarishmaB AndrewN

There is no mention in the question that the vacationers are coming from large metropolitan cities. What if they are coming from a place that has the same number of aquariums and zoos? There is no way we can assume the place where the vacationers are actually coming from and what are the qualities of that place.

Having said that, is B correct just because it helps us provide an answer as to "why" a certain trend is taking place, even if it includes certain information that is well out of scope ?
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Hello, Namangupta1997. We do not need to assume that vacationers are necessarily coming from large metropolitan cities. Rather, answer choice (B) is telling us that many of these large (populous) cities have one type of attraction—zoos—but not the other—aquariums. Thus, many visitors to any given metropolitan zoo could logically be from the surrounding city—i.e. non-visitors. Meanwhile, in order to visit a true aquarium, it would be necessary to have a true aquarium to visit. If there were ten major cities that all had zoos but only three had dedicated aquariums, then any residents from any of the other seven cities who wanted to visit any of the three dedicated aquariums would have to travel—or visit—one of the other cities, to say nothing of visitors from any other locations (e.g., rural areas, towns, or cities without their own pure aquariums or zoos). The information in answer choice (B) is not out of scope. Both halves of the statement, together, help to account for the difference described. Moreover, I see no other compelling answer choice. Is there something you were thinking of that seems more reasonable?

- Andrew
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In the United States, vacationers account for more than half of all vi 31 May 2022, 21:04
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Namangupta1997
Hi KarishmaB AndrewN

There is no mention in the question that the vacationers are coming from large metropolitan cities. What if they are coming from a place that has the same number of aquariums and zoos? There is no way we can assume the place where the vacationers are actually coming from and what are the qualities of that place.

Having said that, is B correct just because it helps us provide an answer as to "why" a certain trend is taking place, even if it includes certain information that is well out of scope ?
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Naman, I am not sure what you mean by 'Option (B) has information that is out of scope." We know that we need to resolve the numbers here so we are looking for some NEW information that will help us explain the discrepancy.
If I know that 50% visitors of pure aquariums are tourists while the number is 25% for zoos, I would likely think of the following factors:
1. Perhaps many locals visit zoos but not so many visit aquariums (Majority of kids may find zoos more fascinating). Tourists are likely to visit both places because they go to visit places in other cities. So higher percentage of visitors of aquariums would be tourists. It can account for the difference in the %ages.
2. Perhaps more tourists like to visit the pure aquarium but not the zoo because their own cities have zoos but not aquariums so aquariums have novelty value. Hence, it can account for the difference in the %ages.
or some other reason.

Option (B) gives us our point 2 above. If most cities have zoos, people likely visit the zoo of their own city. But when they go to other cities, if they have a pure aquarium there, they are likely to visit it. So if there are few pure aquariums, most tourists coming to those cities are likely to visit it and hence it could account for higher %age of tourist visitors for aquariums. Yes, all tourists do not come from big cities only. But we only need to account for 25% difference. At least some of it could be accounted for by big city tourists. Hence, option (B) HELPS explain the numbers, even if it may not completely explain.
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In the United States, vacationers account for more than half of all vi 01 Jun 2022, 01:05
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Hi KarishmaB AndrewN

There is no mention in the question that the vacationers are coming from large metropolitan cities. What if they are coming from a place that has the same number of aquariums and zoos? There is no way we can assume the place where the vacationers are actually coming from and what are the qualities of that place.

Having said that, is B correct just because it helps us provide an answer as to "why" a certain trend is taking place, even if it includes certain information that is well out of scope ?
Hello, Namangupta1997. We do not need to assume that vacationers are necessarily coming from large metropolitan cities. Rather, answer choice (B) is telling us that many of these large (populous) cities have one type of attraction—zoos—but not the other—aquariums. Thus, many visitors to any given metropolitan zoo could logically be from the surrounding city—i.e. non-visitors. Meanwhile, in order to visit a true aquarium, it would be necessary to have a true aquarium to visit. If there were ten major cities that all had zoos but only three had dedicated aquariums, then any residents from any of the other seven cities who wanted to visit any of the three dedicated aquariums would have to travel—or visit—one of the other cities, to say nothing of visitors from any other locations (e.g., rural areas, towns, or cities without their own pure aquariums or zoos). The information in answer choice (B) is not out of scope. Both halves of the statement, together, help to account for the difference described. Moreover, I see no other compelling answer choice. Is there something you were thinking of that seems more reasonable?

- Andrew
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Hi AndrewN

The reason I thought that the choice is out of scope is because it uses some new information. But now I understand that just the presence of new information, however, does not necessarily make an answer choice irrelevant. As you explained, both halves of the statement help us resolve the apparent paradox. Also, I think we also have to see (as Karishma also pointed out) which answer choice COULD help us account for the difference described. There could be some scenarios in which the correct answer choice might not explain the paradox but we have to focus on the possibility in which it CAN help. If all other choices are logically incapable of providing any help to our given conundrum, the answer choice that has the scope of filling the gap, must be correct. Can I extract this indirect learning from this question ?
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Namangupta1997
Hi AndrewN

The reason I thought that the choice is out of scope is because it uses some new information. But now I understand that just the presence of new information, however, does not necessarily make an answer choice irrelevant. As you explained, both halves of the statement help us resolve the apparent paradox. Also, I think we also have to see (as Karishma also pointed out) which answer choice COULD help us account for the difference described. There could be some scenarios in which the correct answer choice might not explain the paradox but we have to focus on the possibility in which it CAN help. If all other choices are logically incapable of providing any help to our given conundrum, the answer choice that has the scope of filling the gap, must be correct. Can I extract this indirect learning from this question ?
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Yes, in a paradox question, you want to encounter new information, and that information should help to logically bridge the gap to resolve the discrepancy. Just as in a strengthen/weaken question, you may be asked to find an answer choice that most strengthens/weakens, in a paradox question, you are frequently tasked with finding what best or most reasonably explains the informational gap. It is rare in CR questions that you are looking for proof: such questions contain the phrase must be true in their stem.

- Andrew
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In Option E - The zoo aquariums of zoos that are in the same city as a pure aquarium tend to be smaller than the aquariums of zoos that have no pure aquarium nearby.

I would want to understand whether the option grammatically correct. Shouldn't we have "IS" after as? At present it seems that Zoos are playing role of pure aquarium, but i think comparison is required that pure aquarium is present in the same city as zoo aquarium.

Please do let me know gap in my understanding.

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In Option E - The zoo aquariums of zoos that are in the same city as a pure aquarium tend to be smaller than the aquariums of zoos that have no pure aquarium nearby.

I would want to understand whether the option grammatically correct. Shouldn't we have "IS" after as? At present it seems that Zoos are playing role of pure aquarium, but i think comparison is required that pure aquarium is present in the same city as zoo aquarium.

Please do let me know gap in my understanding.
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Notice that the point is that the ZOOS are in the same city as a PURE AQUARIUM.

So, the way that idea is expressed is basically fine.

That said, we could argue that we need "is" there because "are" doesn't agree with the singular "pure aquarium."
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