Syllogisms Questions and Answers

Answer: D

Only IV follows.

Conclusion IV, 'Some trees are not sharks', is statement (A) itself, so it follows.

The others do not. Statement (B) says some sharks are not balloons, which directly contradicts I, 'All sharks are balloons'. Nothing in the statements links balloons to trees, so neither II ('All balloons are trees') nor III ('Some trees are balloons') can be concluded. Two negative particular statements give no definite conclusion between trees and balloons.

I and III do not form an either-or pair, because they are not about the same two terms, so 'Only either I or III follows' is also wrong.

Answer: D

Only I, II and IV follow.

I: 'Some google are cottons' converts to 'Some cottons are google', so I follows.

II: the google that are cottons cannot be pillows, because no cottons are pillow. So some google are not pillow, and II follows.

IV: 'No cottons are pillow' means every cotton is outside pillow, and since some cottons exist (statement A), some cottons are not pillow. IV follows.

III, 'Some pillow are google', does not follow: the statements put no pillow inside google. So any option leaving out II or IV, or including III, is wrong.

Answer: A

Only I, II and IV follow.

I: some gadgets are buffaloes, and all buffaloes are witches, so those gadgets are witches. 'Some gadgets are witches' follows.

II and IV: 'All buffaloes are witches' gives 'Some buffaloes are witches' (IV) and, by conversion, 'Some witches are buffaloes' (II). Both follow.

III, 'All witches are buffaloes', reverses the universal statement, which is not allowed: there may be witches that are not buffaloes. 'Only I & II' leaves out IV, 'Only I & III' includes III, and II and III are not an either-or pair.

Answer: C

The answer is Either conclusion I or II follows.

From 'No bird is pen' and 'All pens are hills', nothing definite follows about birds and hills: some hills may or may not be birds. So neither I ('Some hills are birds') nor II ('No hill is bird') follows by itself.

But I and II are a complementary pair about the same two terms: one says some hills are birds, the other that none is. Exactly one of them must be true, so the answer is 'either I or II'. Conclusion III ('Some tables are pens') does not follow, because the tables that are birds cannot be pens, and nothing is said about other tables.

Answer: D

The statements that follow with certainty are (i), (ii) and (iii).

If “Some human beings are not cruel creatures” is false, then there is no human being who is not cruel, so all human beings are cruel creatures: statement (i).

Human beings exist in this world (they are among its creatures), so if all of them are cruel, then some human beings are cruel (ii), and equally some cruel creatures are human beings (iii), which is (ii) read the other way round.

Statement (iv), “No human beings are cruel creatures”, contradicts (i), so any option containing it is wrong. Options listing only (i), or only (i) and (ii), leave out statements that also follow.

Answer: C

The correct option is only conclusion I and conclusion III are correct.

Conclusion I is the converse of Statement 1: if some engineers are writers, then those same people are writers who are engineers, so some writers are engineers. Conclusion III is the converse of Statement 2: “No writer is an actor” means writers and actors do not overlap at all, so no actor is a writer.

Conclusion II does not follow: all actors are engineers, but that does not make all engineers actors. Conclusion IV contradicts Statement 2, so it is false, and the “either III or IV” option is wrong because III is definitely true and IV definitely false, not an either-or pair. Only I is incomplete, since III also follows.

Answer: D

Neither (i) nor (ii) follows.

“All hill-stations have a lake” means every hill-station has at least one lake. It sets a minimum, not a maximum, so a hill-station with two lakes still satisfies it.

Statement (i) does not follow: having two lakes does not stop Ooty from being a hill-station, and nothing says whether it is one. Statement (ii) does not follow either: the premise never limits a hill-station to one lake. Both rest on reading “a lake” as “exactly one lake”.

Answer: B

Only conclusion ii follows.

Some shelves are chairs, and all chairs are benches, so those shelves that are chairs are also benches: at least one shelf is a bench (ii).

The other conclusions do not follow. The tables that are shelves need not be the same shelves that are chairs, so no table need be a bench or a chair, which rules out i and iii. 'All chairs are benches' does not mean 'all benches are chairs'; benches may include things that are not chairs, so iv fails.

That makes 'Only ii' correct, and every option including i, iii or iv wrong.

Answer: D

The certain inference is Some ferocious creatures are creatures with claws.

The passage says creatures with claws exist ('there are also creatures that have claws') and that all of them are ferocious. So at least one ferocious creature has claws, which is exactly the statement.

'All creatures with claws are animals' does not follow: we know animals are ferocious and clawed creatures are ferocious, but nothing says the clawed creatures are animals. 'Some creatures with claws are non-ferocious' and 'some non-ferocious creatures have claws' both contradict the rule that every clawed creature is ferocious.

Answer: C

Neither conclusion I nor II follows.

Statement I keeps managers and leaders apart; statement II puts all leaders inside the set of executives. Nothing says anything about managers and executives directly: managers may be executives who are not leaders, or they may not be executives at all.

So 'No manager is an executive' does not follow, and neither does 'No executive is a manager', which says the same thing. Both are possible but not certain, so options claiming either or both follow are wrong.