Syllogism based Questions | General Intelligence and Reasoning for SSC CGL

What is Syllogism?

The word syllogism is derived from the Greek word “syllogismos” which means “conclusion, inference”. Syllogisms are a logical argument of statements using deductive reasoning to arrive at a conclusion. 

The questions which are asked in this section contain two or more statements, and two or more conclusions follow these statements. One has to find out which of these conclusions logically follow the given statements. The statements have to be taken true even if they seem to be at variance from the commonly known facts.

Directions (1-4): The following questions have a few statements followed by a conclusion. Read the statements and logically select the conclusions that can follow the statements.
Q.1. Statements:

I. Some parrots are scissors.

II. Some scissors are not combs.

Conclusions:

I. Some scissors are parrots.

II. Some combs are parrots.

Correct Answer is Option (a).
Some scissors are parrots (I to I), as the universal principal no. 4 says, that with two particular statements only I to I is possible. Therefore, only 1 conclusion is possible. Nothing else is possible.

Q.2. Statement:
I. All AB are PQs
II. Some PQs are XYs
III. All XYs are MNs
Conclusions:
I. Some ABs are XYs
II. Some MNs are PQs
III. No AB is XY
IV. All  PQs are ABs
a) Only I follows
b) I and II but III follows
c) II and I or III follows
d) All of them follow

Correct Answer is Option (c).

From the venn diagram, we can see that Some MNs are PQs and Some ABs are XYs or No AB is XY by given statements.

Q.3. Statements:
I. Some goats are sheeps.
II. All sheeps are bikes.
Conclusions:
I. All bikes are sheeps.
II. Some bikes are goats.
a) Only I follows
b) Only II follows
c) Either I or II follows
d) Both follow

Correct Answer is Option (b).
 

Q.4. Statements:
I. All greens are blues
II. Some blues are reds
Conclusions:
I. Some blues are greens
II. All greens are reds
a) Only I follows
b) Only II follows
c) Either I or II follows
d) Neither follows

Correct Answer is Option (a).
 
From the venn diagram, we can see that Some blues are greens is the only conclusion which follows the given statements.

Directions for questions 5 and 8: In each of the following questions some statements are given. On basis of the statements determine which conclusion/s is/are true.
Q.5. Statements: 
I. Some pots are trees. 
II. Some trees are scooters. 
III. All cars are pots. 
IV. Some scooters are pots.
Conclusions:
I. All trees are pots.
II. Some pots are cars.
III. No tree is car.
IV. No pot is car.
a) I follows
b) All four follows
c) I and II follows
d) II and III follows

Correct Answer is Option (d).
 
From the venn diagram, we can see that Some pots are cars and No tree is car are the conclusions from given statements.

Q.6. Statements: 
I. All right are black. 
II. All black are boards. 
III. Some black are watches. 
IV. No watch is right.
Conclusions:
I. Some right is watch.
II. No black is watch.
III. Some boards are right.
IV. No watches are black.
a) Only conclusion b follows
b) Only conclusion b follows
c) Only conclusion c follows
d) a, b and c follows

Correct Answer is Option (c).
 
From the venn diagram, we can see that Some boards are right is the only conclusion that follows the given statements.

Q.7. Statements: Some bags are lights. Some doors are bags. All shirts are door. All cups are bag. No soup is cup. Some soups are lights. 
Conclusions:
I. No soup is bag.
II. No shirt is bag.
III. All lights are soup is a possibility.
IV. Some shirts are cup.
a) Either I or II follows
b) Only II follows
c) Either I or III follows
d) II and III follows.

Correct Answer is Option (d). 

We've drawn the venn diagram with the help of given statements. From the diagram we can see that No shirt is bag and All lights are soup is a possibility are the conclusions that follows the given statements. 

Q.8. Statements: Some clothes are paper. All grey are clothes. Some pink are grey. No grey is white.
Conclusions:
I. No white is pink.
II. Some pink is white.
III. Some white are paper.
a) Either I or II follows
b) Only II follows
c) Either I or III follows
d) II and III follow.

Correct Answer is Option (a).
 
We've drawn the venn diagram with the help of given statements. From the diagram we can see that either No white is pink or Some pink is white conclusion follows the given statements.

Directions (9 -10): In each question below are four statements followed by some conclusions. You have to take the given statements to be true even if they seem to be at variance with commonly known facts and then decide which of the given conclusions logically follows from the given statements.
Q.9. Statement I:  All shirts are white.
Statement II:  Some white are pink.
Statement III:  All pink are dresses.
Statement IV:  Some dresses are clothes.
Conclusion I: Some clothes are shirts.
Conclusion II:  Some dresses are shirts.
Conclusion III: Some dresses are white.
Conclusion IV:  All dresses are pink.
a) None follows
b) Only II follows
c) Only III follows
d) Both II and III follow

Correct Answer is Option (c).
 
Conclusion I: Some clothes are shirts.  (X)
Conclusion II: Some dresses are shirts.  (X)
Conclusion III: Some dresses are white.  (✓)
Conclusion IV: All dresses are pink.     (X)

Q.10. Statement I: Some pens are bats.
Statement II: Some bats are boxes.
Statement III: All boxes are pencils.
Statement IV: No pencil is notebooks.
Conclusion I: No pens are notebooks.
Conclusion II: Some pencils are pens.
Conclusion III: Some pencils are bats.
Conclusion IV: No boxes are notebooks.
a) None follow
b) II and III follow
c) Either I or III follow
d) Both III and IV follow

Correct Answer is Option (d).

Conclusion I: No pens are notebooks.  (X)
Conclusion II: Some pencils are pens.  (X)
Conclusion III: Some pencils are bats.  (✓)
Conclusion IV: No boxes are notebooks.  (✓)