In each question below, a few statements are followed by three conclusions.…

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In each question below, a few statements are followed by three conclusions. Treat the statements as true, even if they differ from commonly known facts. Use the convention of this exam that every class named in a universal ‘All A are B’ statement is non-empty. Read all the conclusions and decide which logically follow from the statements.

Statements

  • All chairs are tables.

  • All tables are bottles.

  • Some bottles are jars.

  • No jar is a bucket.

Conclusions

I. It is possible that some tables are jars.

II. Some bottles are chairs.

III. Some bottles are not buckets.

Answer: C. All conclusions followConceptIn categorical syllogisms, treat each universal statement as a set inclusion and each particular statement as proof that at least one member exists. A…

  1. A.

    Only conclusion I is true

  2. B.

    Both conclusions I and II are true

  3. C.

    All conclusions follow

  4. D.

    Only conclusion II is true

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Show answer & explanation

Correct answer: C

Concept

In categorical syllogisms, treat each universal statement as a set inclusion and each particular statement as proof that at least one member exists. A possibility conclusion is admissible when it can be added without contradicting any stated inclusion or exclusion.

This item explicitly stipulates existential import for universal statements: if all A are B, then A is non-empty and some B are A. Also, if some B are C and no C are D, those existing B–C members are not D.

Application

Set diagram showing chairs within tables within bottles, jars overlapping bottles, and jars disjoint from buckets
  1. Let C, T, B, J, and K denote chairs, tables, bottles, jars, and buckets. From C ⊆ T and T ⊆ B, transitivity gives C ⊆ B. Because the stem stipulates that C is non-empty, choose c in C; then c is also in B. Hence some bottles are chairs, so conclusion II follows.

  2. Some bottles are jars, so choose an existing member x in B ∩ J. No jar is a bucket, hence x is not in K. Thus x lies in B but not in K, so conclusion III follows.

  3. No statement forbids T ∩ J. A table may be placed inside the jar region while every jar remains outside the bucket region and C ⊆ T ⊆ B is preserved. Therefore conclusion I is possible.

Cross-check

A consistent model can contain one chair–table–bottle member and one table–bottle–jar member, with every jar outside the bucket set. The explicit non-empty-class convention rules out an empty chair set; the model satisfies all four statements and supports conclusions I, II, and III.

Therefore, all conclusions follow.

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