PrepTest 159, Section 1, Question 10
A recent study found that most individuals believe(25 more words not shown)
Which one of the following(5 more words not shown)
- Asome people believe(10 more words not shown)
- Bmost people are(7 more words not shown)
- Cmost people underestimate(8 more words not shown)
- Dmost people think(10 more words not shown)
- Esome people incorrectly(9 more words not shown)
Reading the argument
Some of these people have to be wrong. They can't all occupy the low-sleep side of the comparison.
Most people think they sleep less than most other people. But, as the passage points out, that description can't actually fit a majority. So the group claiming it is too large for everyone in that group to be correct.
What we’re looking for
How many must be mistaken? We don't know that it's most of them. Imagine 100 people with different sleep times. The 50 shortest sleepers each sleep less than most of the other 99 people. If 51 people claim to qualify, at least one claimant is wrong, but the other 50 could be right. That is enough to support a modest conclusion: some people have an incorrect belief about how their sleep compares with other people's.
Working the answers
- A
Any particular person's belief could be true. You could sleep less than most other people, and so could I. The problem is that too many people claim that position for all their claims to be true together. That isn't the same as saying someone believes an individually impossible proposition.
- B
A person might know exactly how many hours they sleep and be wrong about how much everyone else sleeps. The study concerns a comparison, not simply awareness of one's own hours. B also says most people lack that awareness, which goes beyond the evidence about some mistaken comparisons.
- C
Some people must underestimate their sleep relative to others, but we haven't established that most do. In our 100-person example, just one of the 51 claimants needs to be mistaken. C takes a conclusion about at least some people and expands it to a majority without support.
- D
Sleeping less than other people isn't the same as sleeping less than you should. Someone might think they need relatively little sleep and are getting exactly the right amount. The passage gives no view about recommended or necessary sleep.
- ECorrect
At least some people incorrectly believe they sleep less than most others. That follows from the mismatch between how many people claim the position and how many can actually occupy it. We don't need to identify those people or prove that a majority is mistaken to reach this conclusion.
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