QUESTION TEXT: At the end of 1997 several nations…
QUESTION TYPE: Necessary Assumption
CONCLUSION: It’s likely that most countries that say their oil reserves haven’t changed are wrong.
REASONING: A few countries say their reserves haven’t changed last year. But oil reserves are unlikely to stay the same, year on year.
ANALYSIS: Notice the quantity words “several” and “most” in this stimulus. You must always pay attention to quantity words.
Several is perhaps 3-7 countries. And in the whole world, perhaps 100-150 countries have oil reserves. “Likely” might mean 70% of countries will see a change in reserves. So it’s perfectly possible for it to be “unlikely” that oil reserves remain unchanged, and for 3-7 countries to have oil reserves that didn’t change. 3-7 is a small percentage of the total. So the argument has to assume it’s unlikely for this group to have its reserves unchanged.
- Who cares what happens in one country? The negation of an “any” statement is that one country didn't fit the trend.
Negation: One country is likely to be right that its oil reserves are unchanged.
- CORRECT. The conclusion is about “most” countries. If we negate this answer, we no longer have information about most countries that stated their reserves didn’t change.
Negation: It is likely that only half or less of the countries which claimed unchanged reserves had oil fields that were drained or discovered.
- We don’t care how reserves change (e.g. slowly or quickly). We only care if they did change.
Negation: In 1997, no single country experienced both a a gradual drop and also a sudden rise in oil reserves.
- Who cares what happens in one country?
Negation: One country incorrectly stated its reserves hadn’t changed, but during 1997 it didn’t discover new reserves or drain old ones.
- This answer is irrelevant. We care about whether nations are correct, not whether they have an obligation to be correct.
Negation: A nation can experience changes in its oil reserves without having the obligation to report them correctly.
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