Logical Reasoning: Syllogism

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Practice Questions

Lane B — Logic & decisions Study step 8 of 26 40 MCQs ready Next topic in path →

Concept Explanation

Syllogism questions give two or three categorical statements (All, Some, No) and ask which conclusion must follow. Think in terms of sets: All A are B means A is fully inside B.

Standard forms

All A are B — every A is a B.
Some A are B — at least one A is a B.
No A is B — A and B do not overlap.
Some A are not B — at least one A lies outside B.

Quick rules

All + All chain: All A are B and All B are C ⇒ All A are C.
All + No: All A are B and No B is C ⇒ No A is C.
Some + All: Some A are B and All B are C ⇒ Some A are C.
Some + Some (middle not linked with All/No): usually no definite conclusion.
Draw a quick Venn diagram when the answer is not immediate.

How to solve fast

Label circles for each term; shade “No” and “All” regions.
Check each conclusion against every possible diagram that fits the statements.
For “Only I / Only II / Both / Neither”, test conclusions one at a time.

Q1 Easy

Statements:
1. All pens are pencils.
2. All pencils are erasers.
Conclusions:
I. All pens are erasers.
II. All erasers are pens.
Which is correct?
Q2 Easy

Statements:
1. All cats are dogs.
2. All dogs are tables.
Which conclusion must be true?
Q3 Easy

Statements:
1. Some A are B.
2. All B are C.
Which conclusion follows?
Q4 Easy

Statements:
1. All books are pens.
2. No pen is a copy.
Which conclusion follows?
Q5 Easy

Statements:
1. All A are B.
2. No B is C.
Which conclusion follows?
Q6 Easy

Statements:
1. Some doctors are teachers.
2. All teachers are poor.
Which conclusion follows?
Q7 Easy

Statements:
1. All squares are rectangles.
2. All rectangles are polygons.
Which conclusion follows?
Q8 Easy

Statements:
1. Some politicians are leaders.
2. All leaders are honest.
Which conclusion follows?
Q9 Easy

Statements:
1. All students are girls.
2. No girl is a boy.
Which conclusion follows?
Q10 Easy

Statements:
1. All mangoes are fruits.
2. All fruits are sweet.
Conclusions:
I. All mangoes are sweet.
II. Some sweet are mangoes.
Which is correct?

Q11 Easy

Statements:
1. Some A are B.
2. No B is C.
Which conclusion follows?
Q12 Easy

Statements:
1. All dogs are animals.
2. Some animals are wild.
Conclusions:
I. Some dogs are wild.
II. All wild are dogs.
Which is correct?
Q13 Easy

Statements:
1. All water is liquid.
2. No liquid is solid.
Which conclusion follows?
Q14 Easy

Statements:
1. Some A are B.
2. All A are C.
Which conclusion follows?
Q15 Easy

Statements:
1. All cars are vehicles.
2. All vehicles are machines.
Conclusions:
I. All cars are machines.
II. Some machines are cars.
Which is correct?
Q16 Easy

Statements:
1. No apple is a mango.
2. All mangoes are fruits.
Conclusions:
I. No apple is a fruit.
II. Some fruits are mangoes.
Which is correct?
Q17 Easy

Statements:
1. All A are B.
2. No C is B.
Which conclusion follows?
Q18 Easy

Statements:
1. Some doctors are lawyers.
2. All lawyers are rich.
Conclusions:
I. Some doctors are rich.
II. All rich are doctors.
Which is correct?
Q19 Easy

Statements:
1. All tigers are cats.
2. All cats are mammals.
Which conclusion follows?
Q20 Easy

Statements:
1. No A is B.
2. All C are B.
Which conclusion follows?

Q21 Medium

Statements:
1. No A is B.
2. All B are C.
Conclusions:
I. No A is C.
II. Some C are not A.
Which is correct?
Q22 Medium

Statements:
1. All roses are flowers.
2. Some flowers are red.
Conclusions:
I. Some roses are red.
II. Some red are roses.
Which is correct?
Q23 Medium

Statements:
1. Some M are P.
2. No P is S.
Conclusions:
I. Some M are not S.
II. Some S are not M.
Which is correct?
Q24 Medium

Statements:
1. All keys are locks.
2. Some locks are doors.
Conclusions:
I. Some keys are doors.
II. Some doors are keys.
Which is correct?
Q25 Medium

Statements:
1. No fish is a bird.
2. All birds are wings.
Which conclusion follows?
Q26 Medium

Statements:
1. Some P are Q.
2. Some Q are R.
Conclusions:
I. Some P are R.
II. Some R are P.
Which is correct?
Q27 Medium

Statements:
1. All chairs are tables.
2. Some tables are wood.
Conclusions:
I. Some chairs are wood.
II. Some wood are chairs.
Which is correct?
Q28 Medium

Statements:
1. All A are B.
2. Some B are C.
Conclusions:
I. Some A are C.
II. All A are C.
Which is correct?
Q29 Medium

Statements:
1. No politician is honest.
2. All honest are truthful.
Which conclusion follows?
Q30 Medium

Statements:
1. No A is B.
2. Some C are B.
Which conclusion follows?

Q31 Medium

Statements:
1. All poets are writers.
2. No writer is a singer.
Conclusions:
I. No poet is a singer.
II. Some singers are not poets.
Which is correct?
Q32 Medium

Statements:
1. All A are B.
2. All A are C.
Which conclusion must follow?
Q33 Medium

Statements:
1. All keys are metal.
2. Some metal is gold.
Conclusions:
I. Some keys are gold.
II. Some gold is keys.
Which is correct?
Q34 Medium

Statements:
1. No A is B.
2. All A are C.
Which conclusion follows?
Q35 Medium

Statements:
1. All A are B.
2. Some B are not C.
Which conclusion follows?
Q36 Medium

Statements:
1. All employees are workers.
2. Some workers are absent.
Conclusions:
I. Some employees are absent.
II. Some absent are employees.
Which is correct?
Q37 Medium

Statements:
1. Some M are N.
2. All N are O.
3. No O is P.
Which conclusion follows?
Q38 Hard

Statements:
1. No A is B.
2. No B is C.
Which conclusion must follow?
Q39 Hard

Statements:
1. Some A are B.
2. Some B are C.
3. All C are D.
Which conclusion follows?
Q40 Hard

Statements:
1. Some A are not B.
2. No B is C.
Conclusions:
I. Some A are not C.
II. Some C are not A.
Which is correct?