Logical ReasoningDifficulty: Medium

PT125 S4 Q24 Explanation

Downtown Petropolis boasted

A free, expert breakdown of this official LSAT Logical Reasoning question.

TopicsNecessary Assumption

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Stimulus

Downtown Petropolis boasted over 100 large buildings 5 years ago. Since then, 60 of those buildings have been demolished. Since the number of large buildings in a downtown is an indicator of the economic health of that downtown, in a serious state of economic decline.

What this question is testing

Necessary Assumption

Your task

Find the assumption the argument requires in order for its conclusion to hold.

Common trap

Answers that would help the argument but aren't strictly required (sufficient, not necessary).

Winning move

Negate each choice — the right one breaks the argument when negated.

Reading along? Open the full official question in LawHub — we show a fragment here and keep the reasoning in our own words.

The question
24.

Which one of the following is an assumption required by

Answer choices

  1. Too Strong3% picked this

    The demolitions that have taken place during the past 5 years have been evenly spread

    The argument needs the demolitions to occur, but it does not need them to occur evenly spread out.

  2. Out of Scope5% picked this

    There have never been significantly more than 100 large buildings in

    The number of buildings outside of the time period about which the argument is about is not relevant.

  3. Out of Scope4% picked this

    Most of the buildings demolished during the past 5 years were torn down because they

    The reason why buildings are torn down is not relevant, since it is only the number of buildings that are the determinant of economic health.

  4. Out of Scope8% picked this

    The large buildings demolished over the past 5 years have been replaced with small buildings built

    Small buildings are not relevant to the argument since it is large buildings which indicate the economic health of a downtown.

  5. Correct80% picked this

    Significantly fewer than 60 new large buildings have been built in downtown Petropolis during the

    Why this is right

    This defends the argument from a possibility that would call into question the argument’s conclusion.

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

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