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Syllogisms aptitude questions

Which conclusions follow from the statements, and which only seem to.

0 of 30 solved in this view

Formula sheetSyllogisms: the essentialsFormula sheetSyllogisms: the essentialsShow

Treat each statement as a picture, and judge only what the statements say, never what you know of the world.

Drawing the statements

  • All A are B: circle A inside B. No A is B: separate circles. Some A are B: overlapping circles. Some A are not B: part of A outside B.
  • A conclusion follows only if it holds in every diagram the statements allow; one counter-drawing rejects it.

Rules that save the drawing

  • Conversions: 'Some A are B' gives 'Some B are A'; 'No A is B' gives 'No B is A'; 'All A are B' gives only 'Some B are A'; 'Some A are not B' has no converse.
  • All A are B + All B are C → All A are C.
  • All A are B + No B is C → No A is C.
  • Some A are B + All B are C → Some A are C.
  • Some A are B + No B is C → Some A are not C.
  • No A is B + Some B are C → Some C are not A.
  • Two 'some' statements, or 'All A are B' with 'Some B are C', give nothing definite about A and C.
  • A 'some' premise can only produce a 'some' conclusion.
  • Either–or: if neither conclusion follows alone but the two form a complementary pair, such as 'Some A are C' and 'No A is C', then either one follows.

Questions30

1

All cats are animals

Statements: All cats are animals. All animals are living things. Conclusions: I. All cats are living things. II. All living things are cats.

venn

45s

Easy
2

Some pens are books

Statements: Some pens are books. All books are papers. Conclusions: I. Some pens are papers. II. All papers are books. Which conclusion follows?

some/all

60s

Medium
3

No student is lazy

Statements: No student is lazy. Some lazy people are rich. Conclusions: I. Some rich people are not students. II. No rich person is a student.

negative

90s

Hard
4

All dogs are animals

Statements: All dogs are animals. All animals are living beings. Conclusions: I. All dogs are living beings. II. Some living beings are dogs.

venn

75s

Medium
5

All roses are flowers

Statements: All roses are flowers. Some flowers fade quickly. Conclusions: I. Some roses fade quickly. II. All flowers are roses. Which conclusion follows?

venn

90s

Medium
6

Some books are pens

Statements: Some books are pens. All pens are pencils. Conclusions: I. Some books are pencils. II. All pencils are pens. Which conclusion follows?

some/all

75s

Medium
7

No cat is a dog

Statements: No cat is a dog. All dogs are pets. Conclusions: I. No cat is a pet. II. Some pets are not cats. Which conclusion follows?

negative

105s

Hard
8

All A are B, no B is C

Statements: All students are hardworking. No hardworking person is lazy. Conclusions: I. No student is lazy. II. Some hardworking people are students.

negative

90s

Medium
9

Some doctors are writers

Statements: Some doctors are writers. All writers are educated. Conclusions: I. Some doctors are educated. II. All doctors are educated.

some/all

75s

Medium
10

Feathers and swimming

Statements: All birds have feathers. Some creatures with feathers can swim. Conclusions: I. Some birds can swim. II. All creatures with feathers are birds.

venn

105s

Hard
11

All pens are blue

Statements: All pens are blue. All blue things are attractive. Conclusions: I. All pens are attractive. II. Some attractive things are pens.

venn

75s

Easy
12

No teacher is rich

Statements: No teacher is rich. Some rich people are generous. Conclusions: I. Some generous people are not teachers. II. No generous person is a teacher.

negative

105s

Hard
13

All squares are rectangles

Statements: All squares are rectangles. All rectangles are quadrilaterals. Conclusions: I. All squares are quadrilaterals. II. All quadrilaterals are squares.

venn

60s

Easy
14

Some players are not tall

Statements: All tall people are players. Some players are not tall. Conclusions: I. Some players are tall. II. All players are tall. Which conclusion follows?

some/all

75s

Medium
15

A chain of three

Statements: All pencils are pens. All pens are markers. All markers are erasers. Conclusions: I. All pencils are erasers. II. All erasers are pencils.

venn

75s

Medium
16

Some fruits are apples

Statements: Some fruits are apples. No apple is sour. Conclusions: I. Some fruits are not sour. II. No fruit is sour. Which conclusion follows?

negative

90s

Hard
17

Managers and employees

Statements: All managers are employees. Some employees are shareholders. Conclusions: I. Some managers are shareholders. II. Some shareholders are employees.

some/all

90s

Medium
18

Two unconnected statements

Statements: Some cars are buses. Some buses are trains. Conclusions: I. Some cars are trains. II. No car is a train. Which conclusion follows?

either or

120s

Hard
19

All metals are conductors

Statements: All metals are conductors. Copper is a metal. Conclusions: I. Copper is a conductor. II. All conductors are metals. Which conclusion follows?

venn

60s

Easy
20

Some chairs are tables

Statements: Some chairs are tables. All tables are wooden. Conclusions: I. Some chairs are wooden. II. All wooden things are tables. Which conclusion follows?

some/all

60s

Medium
21

No fish is a mammal

Statements: No fish is a mammal. All whales are mammals. Conclusions: I. No whale is a fish. II. Some mammals are whales. Which conclusion follows?

negative

75s

Medium
22

Poets and writers

Statements: All poets are writers. Some writers are journalists. Conclusions: I. Some poets are journalists. II. Some journalists are writers.

some/all

75s

Medium
23

Two classes inside a third

Statements: All cats are animals. All dogs are animals. Conclusions: I. Some cats are dogs. II. No cat is a dog. Which conclusion follows?

either or

105s

Hard
24

All pens are red

Statements: All pens are red. No red thing is heavy. Conclusions: I. No pen is heavy. II. Some heavy things are pens. Which conclusion follows?

negative

75s

Medium
25

A chain broken by 'some'

Statements: Some doctors are teachers. Some teachers are singers. Conclusions: I. Some doctors are singers. II. Some singers are teachers.

some/all

75s

Medium
26

Engineers and graduates

Statements: All engineers are graduates. Some graduates are unemployed. Conclusions: I. Some engineers are unemployed. II. Some unemployed people are graduates.

some/all

75s

Medium
27

Books and magazines

Statements: No book is a magazine. All magazines are printed. Conclusions: I. Some printed things are not books. II. No printed thing is a book.

negative

90s

Hard
28

A three-step chain

Statements: All mangoes are fruits. All fruits are food. All food is perishable. Conclusions: I. All mangoes are perishable. II.

venn

75s

Medium
29

When neither follows

Statements: Some pens are red. Some red things are expensive. Conclusions: I. Some pens are expensive. II. No pen is expensive. Which conclusion follows?

either or

105s

Hard
30

Testing a converse

Statement: All lawyers are graduates. Conclusions: I. Some graduates are lawyers. II. All graduates are lawyers. Which conclusion follows?

venn

60s

Easy

Showing 30 of 30

Syllogisms Aptitude Questions with Solutions

30 Syllogisms questions with hints, worked solutions and time targets — 5 easy · 16 medium · 9 hard.

  • Section: Logical Reasoning
  • Questions: 30
  • By difficulty: 5 easy · 16 medium · 9 hard
  • Cost: Free, unlimited on every plan

Which conclusions follow from the statements, and which only seem to.

Syllogisms: the essentials

Treat each statement as a picture, and judge only what the statements say, never what you know of the world.

Drawing the statements

  • All A are B: circle A inside B. No A is B: separate circles. Some A are B: overlapping circles. Some A are not B: part of A outside B.
  • A conclusion follows only if it holds in every diagram the statements allow; one counter-drawing rejects it.

Rules that save the drawing

  • Conversions: 'Some A are B' gives 'Some B are A'; 'No A is B' gives 'No B is A'; 'All A are B' gives only 'Some B are A'; 'Some A are not B' has no converse.
  • All A are B + All B are C → All A are C.
  • All A are B + No B is C → No A is C.
  • Some A are B + All B are C → Some A are C.
  • Some A are B + No B is C → Some A are not C.
  • No A is B + Some B are C → Some C are not A.
  • Two 'some' statements, or 'All A are B' with 'Some B are C', give nothing definite about A and C.
  • A 'some' premise can only produce a 'some' conclusion.
  • Either–or: if neither conclusion follows alone but the two form a complementary pair, such as 'Some A are C' and 'No A is C', then either one follows.

Questions

  1. All cats are animals Easy
    Statements: All cats are animals. All animals are living things. Conclusions: I. All cats are living things. II. All living things are cats.
  2. Some pens are books Medium
    Statements: Some pens are books. All books are papers. Conclusions: I. Some pens are papers. II. All papers are books. Which conclusion follows?
  3. No student is lazy Hard
    Statements: No student is lazy. Some lazy people are rich. Conclusions: I. Some rich people are not students. II. No rich person is a student.
  4. All dogs are animals Medium
    Statements: All dogs are animals. All animals are living beings. Conclusions: I. All dogs are living beings. II. Some living beings are dogs.
  5. All roses are flowers Medium
    Statements: All roses are flowers. Some flowers fade quickly. Conclusions: I. Some roses fade quickly. II. All flowers are roses. Which conclusion follows?
  6. Some books are pens Medium
    Statements: Some books are pens. All pens are pencils. Conclusions: I. Some books are pencils. II. All pencils are pens. Which conclusion follows?
  7. No cat is a dog Hard
    Statements: No cat is a dog. All dogs are pets. Conclusions: I. No cat is a pet. II. Some pets are not cats. Which conclusion follows?
  8. All A are B, no B is C Medium
    Statements: All students are hardworking. No hardworking person is lazy. Conclusions: I. No student is lazy. II. Some hardworking people are students.
  9. Some doctors are writers Medium
    Statements: Some doctors are writers. All writers are educated. Conclusions: I. Some doctors are educated. II. All doctors are educated.
  10. Feathers and swimming Hard
    Statements: All birds have feathers. Some creatures with feathers can swim. Conclusions: I. Some birds can swim. II. All creatures with feathers are birds.
  11. All pens are blue Easy
    Statements: All pens are blue. All blue things are attractive. Conclusions: I. All pens are attractive. II. Some attractive things are pens.
  12. No teacher is rich Hard
    Statements: No teacher is rich. Some rich people are generous. Conclusions: I. Some generous people are not teachers. II. No generous person is a teacher.
  13. All squares are rectangles Easy
    Statements: All squares are rectangles. All rectangles are quadrilaterals. Conclusions: I. All squares are quadrilaterals. II. All quadrilaterals are squares.
  14. Some players are not tall Medium
    Statements: All tall people are players. Some players are not tall. Conclusions: I. Some players are tall. II. All players are tall. Which conclusion follows?
  15. A chain of three Medium
    Statements: All pencils are pens. All pens are markers. All markers are erasers. Conclusions: I. All pencils are erasers. II. All erasers are pencils.
  16. Some fruits are apples Hard
    Statements: Some fruits are apples. No apple is sour. Conclusions: I. Some fruits are not sour. II. No fruit is sour. Which conclusion follows?
  17. Managers and employees Medium
    Statements: All managers are employees. Some employees are shareholders. Conclusions: I. Some managers are shareholders. II. Some shareholders are employees.
  18. Two unconnected statements Hard
    Statements: Some cars are buses. Some buses are trains. Conclusions: I. Some cars are trains. II. No car is a train. Which conclusion follows?
  19. All metals are conductors Easy
    Statements: All metals are conductors. Copper is a metal. Conclusions: I. Copper is a conductor. II. All conductors are metals. Which conclusion follows?
  20. Some chairs are tables Medium
    Statements: Some chairs are tables. All tables are wooden. Conclusions: I. Some chairs are wooden. II. All wooden things are tables. Which conclusion follows?
  21. No fish is a mammal Medium
    Statements: No fish is a mammal. All whales are mammals. Conclusions: I. No whale is a fish. II. Some mammals are whales. Which conclusion follows?
  22. Poets and writers Medium
    Statements: All poets are writers. Some writers are journalists. Conclusions: I. Some poets are journalists. II. Some journalists are writers.
  23. Two classes inside a third Hard
    Statements: All cats are animals. All dogs are animals. Conclusions: I. Some cats are dogs. II. No cat is a dog. Which conclusion follows?
  24. All pens are red Medium
    Statements: All pens are red. No red thing is heavy. Conclusions: I. No pen is heavy. II. Some heavy things are pens. Which conclusion follows?
  25. A chain broken by 'some' Medium
    Statements: Some doctors are teachers. Some teachers are singers. Conclusions: I. Some doctors are singers. II. Some singers are teachers.
  26. Engineers and graduates Medium
    Statements: All engineers are graduates. Some graduates are unemployed. Conclusions: I. Some engineers are unemployed. II. Some unemployed people are graduates.
  27. Books and magazines Hard
    Statements: No book is a magazine. All magazines are printed. Conclusions: I. Some printed things are not books. II. No printed thing is a book.
  28. A three-step chain Medium
    Statements: All mangoes are fruits. All fruits are food. All food is perishable. Conclusions: I. All mangoes are perishable. II.
  29. When neither follows Hard
    Statements: Some pens are red. Some red things are expensive. Conclusions: I. Some pens are expensive. II. No pen is expensive. Which conclusion follows?
  30. Testing a converse Easy
    Statement: All lawyers are graduates. Conclusions: I. Some graduates are lawyers. II. All graduates are lawyers. Which conclusion follows?

Placement tests that ask syllogisms