Question
Statement : No paper is a book. All
books are copies. Some copies are pages. No page is a letter. Conclusion: I. Some letters are copies. II. Some books are pages. III. No copy may be paper. IV. Some letters are not copies. In a question given four statements followed by four conclusions numbered I, II and III and IV. You have to take the given statements to be true even if they seem to be at variance with commonly known facts. Read all the conclusions and then decide which of given conclusions logically follows from the given statements disregarding commonly known facts.Solution
Some copies are pages (I) + No page is a letter (E) ⇒ S ome copies are not letters (O). Hence, conclusion II and IV will not follow but it will make a complementary pair. All books are copies (A) + Some copies are pages (I) ⇒ No conclusion. Hence, conclusion II will follow. No paper is a book (E) + All books are copies (A) ⇒ Some copies are not papers (O) ⇒ Probable conclusion ⇒ No copy may be paper (E). Hence, Conclusion III follow. 
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