Difficulty: Medium
Correct Answer: Only (2) and (3)
Explanation:
Introduction / Context:Here we mix two universal statements with one particular statement. The challenge is to see which particular conclusions are compelled by subset relations and which are not forced due to possible non-overlap.
Given Data / Assumptions:
Concept / Approach:“All X are Y” creates subset relations. From a subset relation we can assert “Some Y are X” when existence is implicit in such exam settings. For intersection claims across two subsets of the same superset, we cannot assume overlap unless given or compelled.
Step-by-Step Solution:
(2) Some books are papers: Since all papers are books and papers exist, at least some books are indeed papers. Valid.(3) Some books are purses: We are told some purses are bags, and all bags are books. Hence those purses are books too. So some books are purses. Valid.(1) Some papers are bags: Although both papers and bags are subsets of books, they can be disjoint within B. Nothing forces an overlap. Not valid.Verification / Alternative check:Draw B as a large set containing two non-overlapping regions P and G. Place some elements in R∩G. Then (2) and (3) are satisfied; (1) remains false. All premises still hold, proving (1) does not follow.
Why Other Options Are Wrong:
Common Pitfalls:Assuming that two subsets of the same superset must intersect. They need not. Only explicit intersection statements compel that conclusion.
Final Answer:Only (2) and (3)
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