Statements: Some pens are papers. All papers are books. Conclusions: I. Some pens are books. II. All books are pens.
- (a)Only I follows
- (b)Only II follows
- (c)Both I and II follow
- (d)Neither I nor II follows
Answer
Why
Correct — D. SSC's key marks Neither I nor II follows: it accepts neither conclusion.
Rule: a conclusion follows only if every diagram the statements allow makes it true.
Conclusion II, All books are pens, fails that test. Papers sit wholly inside books, so books may include papers that are not pens, and books that are not papers at all.
On conclusion I, Some pens are books, the key also says no. The standard Some + All rule reads it the other way; the note on the key records that gap → option (d).
Why the others are wrong
- (a)Only I follows — SSC's key rejects Only I because it does not accept conclusion I, Some pens are books. The note on the key sets out why the standard Some + All rule disputes that call.
- (b)Only II follows — All books are pens is not forced: books can include papers that are not pens, and books that are not papers at all. Conclusion II fails under the rule and the key alike.
- (c)Both I and II follow — Both needs conclusion II, and nothing puts every book among the pens. 'All papers are books' does not even reverse to 'All books are papers', so II fails.
Concept
Statements of the shape Some A are B and All B are C link A to C through B, and B sits wholly inside C.
Whatever part of A overlaps B is therefore inside C as well, so 'Some A are C' follows in every diagram. This is the classical syllogism known as Darii.
What does not follow is an 'All' claim about A or C: the statements say nothing about the A's outside B, or the C's outside B.
The key and the rule disagree on conclusion I. SSC's keys accept the same step elsewhere.
At 23 Sep 2025, 16:00, Reasoning Q.9, 'Some cats are dogs. All dogs are animals.' is keyed to make 'Some cats are animals' follow.
At 19 Sep 2024, 16:00, Reasoning Q.19, 'Some shirts are pants. All pants are jackets. All jackets are trousers.' is keyed to make 'Some trousers are shirts' follow.
Key facts
- 'Some A are B' with 'All B are C' gives 'Some A are C'.
- 'Some A are C' converts to 'Some C are A', so 'Some books are pens' holds as well.
- 'All B are C' does not convert to 'All C are B'.
Study next
Common traps
- Reversing 'All papers are books' into 'All books are papers', which makes conclusion II look closer than it is.
- Confusing this pattern with All + Some, where the overlap may fall outside the smaller circle and nothing follows.
The Some + All template is set at 23 Sep 2025, 16:00, Reasoning Q.9 and 19 Sep 2024, 16:00, Reasoning Q.19, where the A-to-C 'Some' conclusion is keyed to follow.
Related PYQs
No directly related past PYQ was found.