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AdamKnewton
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PostThu Feb 03, 2011 1:50 am Thank this user for their post
Very good point -- I was also tempted by (A). The thing is that "most" has a formal logical meaning: it means "more than 50%." Therefore, unless we can clarify that more than half of all the mystery stories in the world match the description in the stimulus, we can't choose (A).
For example, it would be acceptable to say that "NBA players are often over 7 feet in height." There certainly are a lot more 7+ feet people in the NBA than in the regular population! However, it would be inaccurate to say that "most NBA players are over 7 feet in height," since the majority of players aren't.
Similarly, if you see the word "most" in a stimulus, it gives you a lot of information. If I tell you that "Most race-car drivers have one-syllable names," you can deduce that "There are more race-car drivers with one-syllable names than there are with three-syllable names." It's a very powerful word!
Notice the word "some" in the correct answer choice. This is exactly the kind of word you're looking for in an Inference Question (much like the equally good word, "can"). The only formal logical definition of "some" is "more than zero," so as long as we have evidence that one such mystery story matches the description above (we do know this much from the stimulus), it's acceptable.
Takeaways:
1) The words "some" and "can" imply any number, one or more. That's all they imply, so they give very little information if they appear in the stimulus, and are very commonly found in right answers on Inference questions.
2) The word "most" implies greater than half, so if it appears in the stimulus, it tells you a lot, and if it appears in an answer choice, it needs specific evidence to support it.
3) The words "often" and "many" don't really have any formal definition -- don't ascribe to them anything beyond the meaning of "some."
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