Logical ReasoningDifficulty: Medium

PT2 S4 Q15 Explanation

In a large residential building, there is a rule

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

TopicsNecessary Assumption

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Full official LSAT questions are available through LawHub. This page provides LSAT Lab's explanation, strategy, and review tools without republishing the full official question.

Stimulus

In a large residential building, there is a rule that no pets are allowed. A group of pet lovers tried to change that rule but failed. The rule-changing procedure outlined in the building’s regulations states that only if a group of tenants can obtain the signatures of 10 percent of the tenants the pet lovers were voted down on their proposal by the majority of the tenants.

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
15.

The argument depends on which one of the

Answer choices

  1. Correct78% picked this

    The pet lovers succeeded in obtaining the signatures of 10 percent of the tenants

    Why this is right

    Answer A is correct.

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

  2. Trap12% picked this

    The signatures of less than 10 percent of the tenants were obtained on the

  3. Trap3% picked this

    Ninety percent of the tenants are against changing the rule

  4. Trap2% picked this

    The support of 10 percent of the tenants for a rule change ensures that the rule

  5. Trap5% picked this

    The failure of the pet lovers to obtain the signatures of 10 percent of the tenants on their petition for a rule change ensures

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