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Reverse Syllogism Shortcut Tricks Tips & Concept

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Reverse Syllogism Tricks & Tips

With the introduction of new pattern questions on syllogism in Bank exams it has become important to use short method to solve such lengthy syllogism questions. Most of the students use Venn Diagram method to solve syllogism. No doubt the method is easy to use, but it is time taking to solve the new Reverse Syllogism questions by Venn Diagram, in which you have to check each option to satisfy the condition given in the question. So switching to RULES for SOLVING SYLLOGISM is best way to solve such question in short time.

Suppose you take 3 minutes to solve a single question of new pattern syllogism, you can solve the same question in 1 minute using rules after proper practice. In this way you can easily save 6-8 minutes in 5 such questions. You can use this saved time for solving other questions. This time will fetch you extra marks. Extra marks enough to clear sectional cutoff and to score good.

Tricks to Solve Reverse Syllogism

Syllogism is a game played with circles logically. Usually statements will be given and we have to find the appropriate conclusion which follows the statements. In Reverse Syllogism, as the name suggest, Conclusions will be given and we have to find the appropriate statements which satisfies the conclusions.
It may seems like a lengthy process, But if you are strong in basic concepts of syllogism along with some elimination tricks, you can master this topic.
Let us brush up some basic concepts of syllogism with some examples.

Statement: All A is B.
Venn diagram:

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Conclusions:
a) All A is B
b) Some A is B
c) Some B is A
d) All B is not A
e) All B being A is a possibility

Statement: Some A is B. All B is C.
Venn diagram:

Conclusion:
a) Some A is B
b) Some A is C
c) Some C is A
d) Some C is B
e) Some B is C
f) All B is C
g) All C is not B
h) All A being B is a possibility
i) All A being C is a possibility
j) All C being B is a possibility
k) All C being A is a possibility
l) All B being A is a possibility

Let’s discuss the elimination tricks to solve Reverse Syllogism with some examples:

Example.1

Conclusions:

I. All A can never be B
II. Any A which is a D is also C.
Statements:
A. Some A is B. All B is C. Some C is D
B. Some A are D. All A are C. No B is D
C. No A is C. All C are B. Some C is D
D. All A are C. Some C are D. No D is B
E. None of these.

Explanation:

• First let us take a quick scan on the statements
• Take Option A and compare it with conclusion I,  All A can never be BSome A is B. All B is C. Some C is D (Option A is eliminated)
• Take Option C and compare it with conclusion II  Any A which is a D is also C No A is C. All C are B. Some C is D (Option C is eliminated)
• Now we have Option B and D
• Take Option B and compare with both the conclusions.

Some A are D. All A are C. No B is D

• From the Shaded region it is clear that All A can never be B and Any A which is D is also C. (Both conclusions Follows, so Option B is the answer)
• In Exam You can stop once you find the answer.
• But, Now let us take Option D also and check.

All A are C. Some C are D. No D is B

• Here All A can never be B may or may not be true
• Therefore, option D doesn’t follow.

Example. 2

Conclusions:

I. Atleast Some A may be C.

II. All C being B is a Possibility.

Statements:

A. Some A are B. Some B are C. All C are D. No A is D.
B. All A are B. No C is B. Some A is D
C. No C is A .All A are D. Some D is B
D. All A Are B. Some A are D. No D is C
E. None of theseAnswer: Option D

Explanation:

• First let us take a quick scan on the statements
• Take Option B and compare it with conclusion II,  All C being B is a Possibility.  All A are B. No C is B. Some A is D (Option B is Eliminated)
• Take Option C and Compare it with Conclusion I Atleast Some A may be C. No C is A. All A are D. Some D is B (Option C is eliminated)
• Now we have Option A and D
• Take Option A and Compare with both the conclusions

Some A are B. Some B are C. All C are D. No A is D.

• Here conclusion I don’t follow
• Now Let us take Option D and Compare with both the conclusions

All A Are B. Some A are D .No D is C

• Both the Conclusions Follow. To understand the concept more easily, above diagram can be redrawn as.

Preferable method to solve Reverse Syllogisms is Elimination method. In this method, we try to eliminate the options step by a step which cannot be answer. Steps should be taken in eliminating the options are given below.
First, always identify “Universal Negative” conclusion, then eliminate those options which do not have a single universal negative statement.
Secondly, check “Particular Negative” conclusion, then eliminate those options which violates this condition.
Thirdly, check “Universal Positive” conclusion, then eliminate the option which also violate this condition.
In last, check “Particular positive” conclusion, then eliminate the option which also violate this condition.
Let’s discuss it with examples.

Example 1
Conclusion:
(1) No toxic is injection.
(2) Some injections are glucose.

Statements:
(A) All toxic are tablet. No tablet is glucose. Some glucose are medicine. All medicine are injection.
(B) Some toxic are tablet. All tablet are injection. Some injection are glucose. All glucose are medicine.
(C) All tablet are toxic. No injection is toxic. Some glucose are injection. All glucose are medicine.
(D) Some injection are toxic. All injection are tablet. Some toxic are glucose. All glucose are medicine.
(E) Some medicine are toxic. Some toxic are injection. Some injection are tablet. All tablet are glucose.

Solution:
In Reverse Syllogism, Conc.1is Universal negative or disjointed set. So first we will try to find out the option which has the statement following this conclusion.
We can see that, In option B, D and E, there is no negative statement. So these cannot be answer.
In option A and C, there is negative statement. In option C, you can see the statement 2 and statement 3 depict the given conclusion.So, C is the answer.
You can also check option A, but when you have got your answer, there is no use of wasting time.
Now, Question is why I checked first option C?
I checked both option A and C, but in C I found related information to Conclusion, So, I go in detail of it.

Example 2
Conclusion:
(1) No toxic is injection.
(2) Some injection are not glucose.

Statements:
(a) All toxic are syrup. Some syrup are glucose. Some glucose are medicine. All medicine are injection.

(b) Some toxic are syrup. All syrup are injection. Some injection are glucose. All glucose are medicine.
(c) All syrup are toxic. Some toxic are not injection. Some glucose are injection. All glucose are medicine.
(d) Some injection are not toxic. Some injection are not syrup. Some toxic are glucose. All glucose are medicine.
(e) No medicine is syrup. All toxic are medicine. All injection are syrup. No syrup is glucose.

Solution:
In this also conclusions are “No toxic is injection” and “Some injection are not glucose”.
First we will identify the option which has statements depicting “No toxic is injection”.
Except option E, all options do not have any “Universal negative” statement. So our answer will be E.
If you have gone through meritshine video and previous article, you basics have been clear, no need to check of the option E. Still for your convenience let’s check Option E.

We can see that All toxics are medicine, All injections are syrup and no medicine is syrup. So, no toxic is injection.
All injections are syrup and No syrup is glucose. So, no injection is glucose which infers that some injection is not glucose.

Example 3
Conclusion:

(1) All toxic are injection.
(2) Some glucose are not medicine.

Statements:
(A) All toxic are syrup. Some syrup are glucose. Some glucose are injection. All medicine are injection.

(B) All toxic are syrup. All syrup are glucose. Some toxic are not medicine. All glucose are injection.
(C) All syrup are toxic. Some toxic are injection. Some glucose are injection. All glucose are medicine.
(D) Some injection are not toxic. No injection are syrup. No toxic are glucose. All glucose are medicine.
(E) No toxic is syrup. All syrup are glucose. All toxic are medicine. All toxic are injection

Solution:In this there is no universal negative statement. Now, we will first focus on Particular Negative statement.
In option A and option C, there is no negative statement, so these options are eliminated.
In option D, last statement is “All glucose are medicine” given, so it will not be the answer.
Now let’s check option E and B.
In option E, last statement has already depicted the first conclusion, but there is no restriction on Glucose and medicine. So, this will also not be our answer.

We have already eliminated four options. So the remaining will be our answer i.e. B.
Now let’s check option B. But, in exams you don’t need to check when you have elimated four options.

We know “some toxic are not medicine” means atleast one element of toxic is not medicine.
In diagram B.1, all toxic are glucose so, so at least one  element of glucose will not be medicine.

Example 4
Conclusion:
(1) Some car are bus.
(2) No bus is plane.
(3) All plane are train

Statement:
(A) Some car are not plane. All drum are train. Some bus are not plane. All planes are drums.

(B) Some bus are car. All bus are train. No plane is bus. All car are train.
(C) Some bus are car. Some car are plane. Some train are plane. No plane is bus.
(D) All bus are train. All plane are drum. Some bus are car. All drum are bus.
(E) All drum are train. No train is car. All bus are car. All plane are drum.

Solution:
In given conclusions, Conc.2 is universal negative type. So, we will first identify options which have this type of statement.
Option B, C and E are this type of statement, so options A and D are eliminated.
In option B and C, statement “No plane is bus” available. Let’s first see these both option.
In option B, there is no relation between plane and train. This option is also eliminated.
In option C, If we check Conc.3 “All plane are train” which is universal affirmative for it statements should be also universal affirmative. So, this option is also eliminated.
So, answer is E. Let’s check it also.

Certain Controversy

 Case Solution 1 Does restatement follows? As explained on Day 5 The Rule is 1) Restatement Follows 2) Possibility of Restatement Doesn’t Follows Example: Statement: Some A are B Conclusion: Some A are B(Follows) Some A are B is a possibility(Doesn’t Follows) 2. Does Some A is B means Some A are Not B or vice versa? NO. It does not means. 3. Does All + No makes complimentary pair? NO. They don’t. On Day 5 we have covered this topic 4. The statement All A are Not B ??? What does it means This is a controversial statement which can have two meaning. So you will never get this statement in exam.

Certain Special words used in Syllogism and their meaning

 Terms Meaning Example Atleast, Most, Many, few SOME Atleast some A are B* OR Most A are B OR Many A are B OR Few A are B => Some A are B *In exams you will mostly find the case of Atleast. Only Statement: Only A is B Conclusion: All B is A

Practice Problems On Syllogism

Direction (1-5): Each option contains some statements. Determine from which statements the given two conclusions follow.

1. Conclusions:
I. All dog being tiger is a possibility
II. Some tiger are not lion
Statements:
A) Some tiger is cat. All cat is lion. No lion is dog
B) No tiger is cat. Some cat is lion. Some cat is dog
C) All dog is cat. No cat is tiger. Some cat is lion
D) No lion is cat. Some cat is tiger. No cat is dog
E) None is correct
Option D
2. Conclusions:
I. Some Blue are Green
II. No red is White
Statements:
A) All blue are red. All red are green. Some green is white
B) All red is green. No green is white. All white is blue
C) All blue is red. Some red are green. All green is white
D) Some blue are red. All red is green. No green is white
E) None is correct
Option D
Solution:
In D) For I. Some blue are green. All red is green => Some+ All= Some=> Some blue are green
For II. All red is green. No green is white => All+ No = No=> No red is white
3. Conclusions:
I. All dollar are euro is a possibility
II. Some pound are dollar.
Statements:
A) Some dollar are rupee. No rupee is pound. Some pound are euro.
B) Some dollar are rupee. All rupee are pound. No rupee is euro.
C) Some dollar are rupee. All rupee are pound. Some pound are euro.
D) All dollar are rupee. Some rupee are pound. Some pound are euro.
E) None of these
Option C
Solution
:

In C)
I. Some + All = Some
Some + Some = No Conclusion but possibility is true so I follow.
II. Some + All = Some. => Some dollar are pound. Reverse Some pound are dollar is true
4. Conclusions:
I. Some pencil are eraser
II. No scale is pen
Statements:
A) No scale is pencil. Some pencil are pen. All pen is pencil
B) All pen is pencil. No pencil is scale. All scale is eraser
C) Some pencil are scale. All scale is eraser. No eraser is pen
D) Some scale are pencil. No pencil is pen. All pen is eraser
E) None is correct
Option C
Solution:
In C) For I. Some pencil are scale. All scale is eraser=> Some + All = Some=> Some pencil are eraser
For II. All scale is eraser. No eraser is pen => All+No= No=> No scale is pen
5. Conclusions:
I. Some white are red is a possibility
II. No red is blue
Statements:
A) Some white are green. No green is red. All blue is green
B) Some red is green. No green is white. All white is blue
C) No blue is green. All green is red. Some green are white
D) Some white are blue. Some blue are red. All red are green.
E) None is correct
Option A
Solution
:

In A) For I. Some white are green. No green is red.=> Some+ No= Some Not=> Some white are not red => Some white are red is a possibility
For II. All blue is green. No green is red.=> All + No => No blue is red => No red is blue

Direction (6-10):  In the following question, a set of four statements is followed by five conclusions, one of which definitely does not follow (or is not a possibility of occurrence). Choose that conclusion as the answer.

1. Statements: Some red are green. All green are blue. No blue is yellow. All yellow is black.
Conclusions:
I.  Some black are not blue
II. Some yellow is green
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option B
2. Statements: All green are white. No white is red. Some red is yellow. No yellow is orange
Conclusions:
I. All red being orange is a possibility
II.  Some yellow are red
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option A
3. Statements: No cat is dog. All dog is lion. No lion is tiger. Some tiger are rabbit
Conclusions:
I. All lion being dog is a possibility
II. All rabbit is lion
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option B
4. Statements: Some rabbit is lion. All lion is monkey. All monkey is tiger. No tiger is dog
Conclusions:
I. Some monkey is dog
II. All rabbit are dog
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option E
5. Statements: All dog is cat. All cat is rat. No rat is lion. All lion is tiger
Conclusions:
I. Some cat are not lion

II. All rat being tiger is a possibility
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option D

Directions: In the following question, a set of four statements is followed by five conclusions, one of which definitely does not follow (or is not a possibility of occurrence). Choose that conclusion as the answer.

1. Statements: Some lions are tigers. Some monkeys are dogs. All dogs are cats. No monkey is lion
Conclusions:
I. All cats are tigers
II. All dogs are lions
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option B
Solution:
If all dogs are lions, then some lions will be monkeys but no lion is monkey so II is definitely false.
2. Statements: All yellow are red. All red are brown. Some green are red. Some white are yellow.
Conclusions:
I. All dogs  are tigers
II. No green is yellow
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option D
3. Statements: Some copy are paste. Some clip are paste. No paste is cut. All add are cut.
Conclusions:
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option A
4. Statements: Some add are subtract. Some divide are subtract. All divide are multiply. No bracket is subtract.
Conclusions:
I. No divide is bracket
II. All bracket are add is a possibility
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option D
5. Statements: All yellow are red. Some brown are yellow. No brown is white. All green are white.
Conclusions:
I. Some green are yellow
II. No red is white
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option D
6. Statements: All lions are tigers. Some dogs are tigers. No cat is dog. All monkey are cat.
Conclusions:
I. All tigers are cats
II. All monkey are tigers
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option A
7. Statements: All A are B. Some A are C. No C is E. All D are E.
Conclusions:
I. Some D are C
II. Some A are D
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option A
Solution:
No C is E, so some D are C is definitely false
8. Statements: Some A are B. All B are C. No C is D. All D are E.
Conclusions:
I. All A are E
II. Some B are D
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option B
9. Statements: Some A are B. All A are C. Some B are D. No B is E.
Conclusions:
I.No A is E
II. All E are C.
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option D
10. Statements: Some A are B. All C are D. No B is D. All D are E.
Conclusions:
I. All A are D
II. Some C are B
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option E
Solution:
I. If all A are D, then some B will be D which is false

II. Similarly II definitely not follows

1. Statements: Some red are green. All red are blue. No red is white.
Conclusions:
I. All white are blue is a possibility.
II. All green are white is a possibility.
A) only I follows
B) only II follows
C) either I or II follows
D) neither I nor II follow
E) both I and II follow
Option A
2. Statements: Some pets are good. Some good are fine. All tricks are fine. No good is bad.
Conclusions:
I. All pets are bad is a possibility.
II. Some tricks are good.
A) only I follows
B) only II follows
C) either I or II follows
D) neither I nor II follow
E) both I and II follow
Option D
3. Statements:Some waters are plants. All plants are pots. Some pots are roots. All roots are stems.
Conclusions:
I. Some roots are not waters
II. All roots being plants is a possibility.
A) neither I nor II follow
B) only I follows
C) either I or II follows
D) only II follows
E) both I and II follow
Option D
4. Statements: Some sites are roads. No site is door. All roads are narrow.
Conclusions:
I. At least some roads are doors.
II. Some narrow are doors is a possibility.
A) only I follows
B) only II follows
C) either I or II follows
D) neither I nor II follow
E) both I and II follow
Option B
5. Statements: All foods are trees. No tree is a stem. Some stems are roots.
Conclusions:
I. Some trees are foods
II. No stem is food
I. Some trees are foods
II. No stem is food
A) only I follows
B) only II follows
C) either I or II follows
D) neither I nor II follow
E) both I and II follow
Option E
6. Statements: All blue are white. No blue is green. Some green are black.
Conclusions:
I. No blue is black
II. Some green are white is a possibility
A) Both I and II follow
B) Neither I nor II follow
C) Only I follows
D) Either I or II follows
E) Only II follows
Option E
7. Statements:All fonts are styles. All styles are paras.Someparas are boards. Some boards are files.
Conclusions:
I. Some paras are fonts.
II. Some files are paras
A) only I follows
B) only II follows
C) either I or II follows
D) neither I nor II follow
E) both I and II follow
Option A
8. Statements:Some tigers are lions. All tigers are rats. No lion is dog. All cats are dogs.
Conclusions:
I. All tigers are cats is a possibility.
II. No cat is lion.
A) only I follows
B) only II follows
C) either I or II follows
D) neither I nor II follow
E) both I and II follow
Option B
9. Statements: Some sites are roads. No site is door. All roads are narrow.
Conclusions:
I. At least some roads are doors.
II. Some narrow are doors is a possibility.
A) only I follows
B) only II follows
C) either I or II follows
D) neither I nor II follow
E) both I and II follow
Option B
10. Statements: Some pets are good. Some good are fine. All tricks are fine. No good is bad.
Conclusions:
I. All pets are bad is a possibility.
II. Some tricks are good.
A) only I follows
B) only II follows
C) either I or II follows
D) neither I nor II follow
E) both I and II follow
Option D

Directions (1-3): In each of the questions below, statements are given followed by two conclusions numbered I and II. Read all the conclusions and then decide which of the given conclusions DEFINITELY DO NOT follow from the given statements.

1. Statements: All chairs are tables. Some tables are pens. No table is pencil. Some pencils are erasers.
Conclusions:
I. Some chairs are pencils
II. All pens are pencils
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option E
2. Statements: All pigs are cats. Some pigs are dogs. No dog is tiger. All lions are tigers
Conclusions:
I. No cat is lion
II. All lions are pigs
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option D
3. Statements: Some chairs are tables. All tables are pens. Some pens are pencils. No pen is eraser.
Conclusions:
I. Some tables are erasers
II. All pencil are eraser
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option E

Directions (4-7): In each of the questions below, statements are given followed by two conclusions numbered I and II. Read all the conclusions and then decide which of the given conclusions follow from the given statements.

1. Statements: All green are orange. Some orange are pink. All pink are white. Some red are pink.
Conclusions:
I. Some orange are white.
II. No green is red.
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option A
2. Statements: Some copy are pen. All pen are erasers. No book is eraser. Some pencils are books.
Conclusions:
I. Some pens are books
II. All pencils are pens is a possibility.
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option D
3. Statements: All chairs are tables. Some pens are chairs. No pencil is pen. All pencils are erasers.
Conclusions:
I. All chairs are erasers is a possibility.
II. Some pencils are chairs.
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option A
4. Statements: All green are white. Some green are black. No blue is green. All red are blue.
Conclusions:
I. No white is red.
II. All black are red is a possibility.
A) only I
B) only II
C) either I or II
D) neither I nor II
E) both I and II
Option D

Direction (8-10): Each option contains some statements. Determine from which statements the given two conclusions follow.

1. Conclusions:
I. Some pens are pencils is a possibility
II. All copy are pencils is a possibility
A) Some copy are pen. All pen are eraser. No pencil is eraser. Some pencils are books.
B) All erasers are copy. Some eraser are pen. No pencil is eraser. All books are pencils.
C) All copy are pen. Some eraser are pen. No book is eraser. All pencils are books.
D) Some copy are pen. Some eraser are pen. No book is pen. All pencils are books.
E) both I and II
Option C
2. Conclusions:
I. All white are blue is a possibility.
II. Some black are not red.
A) All white are black.Some green are black. Some red are green. No black is blue.
B) Some white are black. All black are green. No red is green. Some red are blue
C) Some white are black. All black are green. Some red are green. Some red are blue
D) All white are black. Some white are green. No blue is green. Some red are blue.
E) both I and II
Option B
3. Conclusions:
I. No cat is pig.
II. All pig are rabbit is a possibility.
A) All monkey are cats. Some cats are lions. Some lions are rabbits. No pig is lion.
B) All monkey are cats. No monkey is lion. All lions are rabbits. Some pigs are lion.
C) Some monkey are cats. Some lions are cats. All rabbits are lions. No pig is lion.
D) Some monkey are cats. All cats are lions. Some lions are rabbits. No pig is lion.
E) both I and II
Option D