Logical Reasoning

PT15 · S3 · Q22 In Sheldon most bicyclists aged 18

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In Sheldon most bicyclists aged 18 and over have lights on their bicycles, whereas most bicyclists under the age of 18 do not.

Conclusion

It follows that most bicyclists who have lights are 18 and up.

Evidence

Most of the bikers 18 and up have lights.

Most of the bikers under 18 do not have lights.

Evaluate

The flaw is a percentage versus number flaw. The argument assumes that because a larger percentage of one group has a particular feature, it must mean a larger number of them have it, ignoring the actual size of the respective groups. Even if a larger percentage of older bikers have lights, in raw numbers, kids with lights can still outnumber them due to the larger population of younger bikers.

Goal

We're looking for an answer choice that presents the same flawed reasoning, which is assuming that a larger percentage implies a larger raw number, without considering the size of the groups being compared.

22.

Which one of the following exhibits a pattern of flawed reasoning most similar to that in the argument above?

  1. Most of the people in

    Bad Evidence Match

    Choice A has a misalignment of quantifiers, moving between most and less than half, which doesn't fit our pattern. The premises here discuss the same group without any opposing groups. The original premises discussed 18 and up vs. under 18.

    1% picked this

  2. The Sheldon Library lent more

    Bad Evidence Match

    Choice B only offers one premise and lacks a necessary comparative structure with opposing group quantifiers that would mirror the flaw.

    0% picked this

  3. Correct

    Most of the residents of

    Why this is right

    Choice C mirrors the original argument with three most claims, comparing those who voted and those who did not, paralleling bikers with and without lights, while assuming the larger percentage means a larger number.

    Skill tested: Parallel Flaw · how this choice captures the argument's function is the move to repeat next time.

    76% picked this

  4. In the county where Sheldon

    Bad Evidence Match

    Choice D uses 'every' and 'not every,' which doesn't emulate the required 'most' structure from the original argument.

    16% picked this

  5. In Sheldon everyone over the

    Bad Evidence Match

    Choice E repeats premises about the same group rather than contrasting groups and doesn't facilitate an overlap similar to the original flawed inference.

    6% picked this

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