Don’t read further, until and unless you’ve mastered the 2-statement syllogism technique explained in previous article (click ME)
- Recap of 2-Statement syllogism
- Parent Statements
- Chain formula
- DemoQ: Married Student Dancers (CSAT-2012)
- DemoQ: Rich n Sick Air travellers (CSAT-2012)
- DemoQ: Drug addict Artists (CSAT-2012)
Recap of 2-Statement syllogism
Before we understand the 3-statement syllogism, let’s recap the 2-statement trick just for refreshing your memory.
What to do when 2-statement syllogism question is given?
- They must have only three terms (A, B and C)
- Are the question statements in standard format (A to B then B to C)? if no, then refer to following conversion table. (important: priority order for conversion is PP>UN>UP.)
Type | Valid Conversion |
Universal Positive (UP) | Only PP |
Universal Negative (UN) | PN or UN |
Particular Positive (PP) | Only PP |
Particular Negative (PN) | Can’t do. |
3. Classify the Question statement (UP, UN, PP, PN)
4. Apply the combo rules on Question statements.
No conclusion scenario |
possible conclusion scenario |
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|
5. (rarely required): if no-conclusion and “either or” given in answer, then check for Complimentary case.
Now we’ll see how to solve three-statement syllogism.
Parent Statements
The crux of 2-statement syllogism was
- When we’ve Question statements in standard format (A to B then B to C).
- We apply some combo rules and may get a conclusion in the form of A to C
(or we may get the conclusion in form of “C to A”, in case the question statements were in the format of UN+(UP/PP). Recall the Ban-ki-Moon’s mood reversal).
In case of three statement syllogism, we accept the conclusion statement (A to C) as valid, then try to find out its parents (those question statements A to B then B to C).
Then, we try to get a valid conclusion out of those two-question statements and see if it matches with the given conclusion state in answer.
No need to get confused, let’s try with a simple scenario.
question statement |
conclusion statement |
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|
Answer choices
- Only 1 and 2
- Only 1, 2 and 3
- All follow
- None Follow
Start with first conclusion statement
i) Some tigers are cats (PP)
Q. if this is a valid conclusion, who’re its parents?
Ans. Thouse question statements with words “tigers”, “cats”, and a common term.
You can see, first and third statement fits the bill.
Q.statement | Type |
|
UP |
|
UP |
- Three terms=Ofcourse yes.
- Are they in standard format (A to B then B to C)? Yes.
- Then what are you waiting for? Just apply the combo rules. UP meets UP then its size doesn’t increase (UP+UP=UP) A to C. Hence conclusion will be “All cats are tigers.” (meaning given conclusion statement #3 is valid).
- If we convert this valid conclusion “All cats are tigers (UP)”, then UP–>PP= Some tigers are cats.
It means the given conclusion statement#1 is also valid.
So far: 1 and 3 are correct.
Now test the second conclusion statement.
Chain formula
ii) some pigs are tigers
if this is a valid conclusion, who’re its parents?
Ans. . Thouse question statements with words “pigs”, “tigers”, and a common term(B).
But I don’t see any such question statements.
Now we’ll have to apply chain formula. Meaning, (A to B1, then B1 to B2, then B2 to C).
Consider this arrangement
Question statements (CHAIN) | Chain |
|
Pig to Cat, cat to dog and finally dog to tiger. Let’s see if we connect pig to tiger. |
|
|
|
We’ll take two statements at time and try to get an intermediate conclusion.
Statement | Type |
|
Particular positive (PP) |
|
Universal positive (UP) |
Three terms = yes
Standard format= yes. (there A to B1 and then B1 to B2, which is just like A to B then B to C)
Apply combo-rule
PP+UP=PP (NASA mood change!) (A to B2)
Hence intermediate conclusion is Some pigs(A) are dogs(B2)
Now take this intermediate conclusion with the next statement in our chain.
Question-statements | Type |
Some pigs(A) are dogs(B2) | Particular positive (PP) (derived) |
All dogs(B2) are tigers(C) | Universal positive (UP) (given in question). |
Again, same standard operating procedure of 2-statement syllogism.
Three terms = yes
Standard format= yes. (there A to B2 and then B2 to C, which is just like A to B then B to C)
Apply combo-rule
Again, PP+UP=PP (NASA mood change!) (A to C)
Therefore conclusion is Some pigs(A) are tigers (C).
Voila! Second conclusion statement is also correct.
So far 1, 2 and 3 are correct.
Let’s check the last statement (IV).
iv) some cats are not tigers
while we were checking the first conclusion statement, we had found that “All cats are tigers (UP)”. Therefore, given conclusion statement is not possible.
Final answer: only 1, 2 and 3 are correct. (option b)
DemoQ: Married Student Dancers (CSAT-2012)
Question statements
- None but students are the members of the club.
- Some members of the club are married.
- All married persons are invited for dance.
Which one of the conclusions can be drawn from the above statements?
- All students are invited for dance
- All married students are invited for dance
- All members of the club are married person
- None of the above conclusions can be drawn
Solution and approach
- first, rephrase the given statements so that processing becomes easier.
- Recall the “special conversion” rule from previous article on 2 statement.
- None but Politicians(A) are honest(B)=> All honest(B) are politicians(A) (Universal positive)
- I’m replacing the word “members of the club” with “club-members”.
- Thus simplified version of the given question is following
Question statements | Answer statements |
1. All clubmembers are students.2. Some clubmembers are married. 3. All married are invited for Dance. |
a) All students are invited for danceb) All married students are invited for dance c) All club-members are married. d) None of the above conclusions can be drawn |
Ok now what?
We’ve to pick up the answer statement one by one and test them.
a) All students are invited for dance
there are two ways to solve this statement, first the
longcut method
Who’re the parents of this conclusion statement?
No direct parents. We’ve to apply chainrule.
Question statements | Chain rule |
|
We’ll try to link students-clubmembers-married-dance invitation. |
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|
|
Let’s start. First two statements
|
UP |
|
PP |
Standard format? Nope.
Conversion needed: yes. But priority order=PP>UN>UP. Means we’ll convert the second statement (particular positive)
|
UP |
|
PP converted to PP. |
They’re still not in standard format. So Exchange positions
|
PP converted to PP. |
|
UP |
Ok now they’re in standard format. Apply the combo rule. PP+UP=PP (NASA Mood change)
Some married are students. This is our intermediate conclusion. Now pair it up with third question statement from the chain rule
Some married(B2) are students(A) | PP |
All married(B2) are invited for Dance.(C) | UP |
Standard format? Nope.
Then convert!
Some students(A) are married(B2) | PP |
All married(B2) are invited for Dance.(C) | UP |
Ok now in standard format (A to B then B to C)
Apply combo rule PP+UP=PP (NASA mood change again!)
Conclusion = Some students are invited for dance. (PP)
But the given answer statement says “All students are invited for dance”(UP)=impossible.
Hence first answer choice is eliminated.
Shortcut
- You see the conclusion statement says “all students are invited for Dance.” (univ.positive statement).
- When do we get “universal positive” statement as conclusion.?
- Only when UP+UP=UP.
- If we apply the chain-rule, we’ll encounter one particular positive (PP). And that’ll ruin the mood (because whenever particular positive statement comes, the conclusion is either
1. PP+UP=Particular positive (NASA mood change) OR
2. UP+PP=No conclusion. (UP politicians hate particular statements).
- Hence we can never get a Universal positive (UP) type of conclusion, in either case! Means this answer choice is invalid by default! No need to manully apply chain rule here. Anyways, Move to the next answer choice
b) All married students are invited for dance
superficially this statement contains three terms.
- Married
- Student
- Dance
Wait a minute! Our syllogism conclusions contain only two terms (e.g. All dogs are cats.)
So, how can we apply syllogism here?
Well, if you observe carefully, the syllogism rules are still applicable in this conclusion statement containing three terms.
From the “longcut” method in previous option, we’ve found that “Some students are invited for dance. (PP)”
- Question: which students are invited? Well, we eliminated the middle-term (B2) “Married”. Means all married students are invited for dance. (this represents the intersecting area between two Venn Diagram circles).
- Therefore, we can say “All married students are invited for dance.” Hence Answer is (B).
c) All club-members are married.(UP)
The second question statement says, “Some clubmembers are married.” (PP).
A particular positive statement can be converted into only PP. Hence we cannot say for sure that all club members are married. Hence this answer choice is incorrect.
DemoQ: Rich n Sick Air travellers (CSAT-2012)
Question Statements
- None but the rich ran afford air-travel.
- Some of those who travel by air become sick
- Some of those who become sick require treatment
Conclusion statements
- All the rich persons travel by air.
- Those who travel by air become sick
- All the rich persons become sick.
- All those who travel by air are rich
Solution
- first we will simplify the given statements.
- Recall the “special conversion” rule from earlier article on 2-statement syllogism.
- None but Politicians(A) are honest.(B)=> All honest(B) are politicians(A) (Universal positive)
- Similarly, None but the rich ran afford air-travel=> All air-travellers are rich. (UP).
- That means, Correct answer is (D). Case is over.
- But just for concept clarity, let’s test remaining answer choices as well.
Simplified question statements
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Simplified Answer statements
|
Now let’s solve
|
The given question statement is “All air-travellers(A) are rich.(B)”(UP). Apply the conversion here, UP=>PP. Hence Some rich(B) are air-travellers(A).Therefore, first answer choice is incorrect. |
|
Question statement #2 says “Some air travellers are sick.” (PP). can’t convert to UP.Hence this option is also incorrect. |
c) All rich are sick.
Q.If this is the conclusion statement, then who are its parents?
Ans. Those question statements which contain the terms “rich”, “sick”, along with a common middle term.
From the given question statements, following two fit the bill
1. All air-travellers(B) are rich | UP |
2. Some air travellers(B) are sick | PP |
Approach #1 (shortcut)
Please observe: “All rich are sick.”= Universal positive statement.
When do we get UP conclusion? Only when combo rule UP+UP=UP is applied.
Now in above case, one question statement is PP. so it’ll “kill” the mood. UP conclusion is not possible. (no need to convert any statement.)
Approach #2 (longcut)
1. All air-travellers(B) are rich.(A) | UP |
2. Some air travellers(B) are sick.(C) | PP |
As you can see, there is one middle term (air travellers). But the question statements are not in standard format (A to B then B to C).
It means, we must convert anyone statement. But priority for conversion is PP>UN>UP.
So we will convert second statement.
Some air-travellers are sick (PP)==convert==> Some sick are air-travellers(B)
1. All air-travellers(B) are rich. | UP |
2. Some sick are air-travellers(B) | PP |
But they are still not in standard format (A to B then B to C). well no problem, just exchange position of question statements
1.Some sick(A) are air-travellers(B) | PP |
2. All air-travellers(B) are rich.(C) | UP |
Apply the Combo-rule. PP+UP=PP (NASA Mood change).
Hence Some sick(A) are rich.(C). (PP)
If we convert it then Some rich are sick. (PP convert to PP).
But answer choice says All rich are sick.= this is not possible.
Therefore, third answer choice is also incorrect.
DemoQ: Drug addict Artists (CSAT-2012)
Question statements
- All artists are whimsical.
- Some artists are drug addicts.
- Frustrated people are prone to become drug addicts.
From the above three statements it may be concluded that:
- Artists are frustrated
- Some drug addicts are whimsical
- All frustrated people are drug addicts.
- Whimsical people are generally frustrated
Statement 3 says “Frustrated people are prone to become drug addicts.” For our purpose this is a “Particular positive (PP)” statement. Let’s simplify it to “Some frustrated people are drug addicts” Now start with answer (A)
a) (all) Artists are frustrated (UP)
if this is the answer, then what could be the question statements?
The question statements could be those statements where the words Artist and frustrated come along with a common middle-term (B)
Consider these question statements:
2. Some artists are drug addicts.(B) | PP |
3. Some Frustrated people are drug addicts.(B) | PP |
Although this in not in “standard format”, but even when we convert one of them (PP->PP), we’ll be left with PP+PP=no conclusion.
Hence move to next option.
b) Some drug addicts are whimsical
- if this is the answer, then what could be the question statements?
- The question statements could be those statements where the words drug addict and whimsical come along with a common middle-term (B)
- Consider these question statements:
1. All artists (B) are whimsical. | UP |
2. Some artists (B) are drug addicts. | PP |
- Three terms = yes.
- Standard format (A to B then B to C)=No.
- So maybe to convert anyone know the statement. according to the priority order PP>UN>UP, we must convert second statement.
1. All artists (B) are whimsical. | UP |
2. Some drug addicts are artists (B). | PP->PP converted. |
Now interchange position of question statement 1 and 2.
Some drug addicts(A) are artists (B). | PP->PP converted. |
All artists (B) are whimsical.(C) | UP |
- Okay now what? Apply the combo rules
- PP+UP=PP. (NASA mood change).
- Thus final answer is “some drug addicts are whimsical.” (option B)
For the archive of all [Aptitude] articles, visit Mrunal.org/aptitude.
statements:
all men are bottle
all bottles are gains
conclusions:
1. some men are bottle
2. some bottle being men is a possibility
ans 1. 1 follows
2.only 2 follows
3.either 1 or 2 follows
4’neither 1 or 2 follows
only 1 follows cause some bottle being men is not a poss. but it z trth
If the statement is given :
Statements: All eraser are not sharpener.
Conclusions:
some sharpener not being eraser is a possibility.
True or Fales ? plssssss reply
I could not find explanations like your’s in arun sharma logical reasoning for syllogism.
thanks a ton !!!
keep it coming ….
once again thank you sir.
pls answer this syllogism:
Statement : a)all actors are male
b)some artists are males
c)all singers are artists
Conclusion : 1)some artist are actors
2)some singers are males
3)some males are actors
4)no singers are males
a)only either 2 or 4 and 3 follow
b)only either 2 or 4 and 1 follow
c)only either 1 or 2 and 4 follow
d)none follow
e)none of these
Mrunal sir , Here in above question , According to me the answer is ‘a’ because it satisfies the complementary conditions ( From your article) ..
But the answer given in the textbook is ‘e’
Please explain me why the answer is ‘e’ and not ‘a’.
IM fully confused …help
1. Statement.
Some People are good.
Some good are not bad.
All bad are human beings.
Conclusion:
I. All People are bad is a possibility
II. At least some Human being are people.
III. No human being is good
(1) Only I follows
(2) Only I & III follows
(3) Only II follows
(4) Either I or II and III follows
(5) None of these
plz anyone help in this.. what do we mean by there is a possiblity.. is it a UP or PN
Mac 07 answer should be a.
In demo question 4, where statement 3 reads ‘frustrated people are prone to become drug addicts’, how do we come to the simplified conclusion that it’s ‘some frustrated people are drug addict’, a PP statement? . If there are no words (to enable us to come to a PP/UP statement) in the beginning such as this, how do we know whether its UP or PP?
In demo question 4, where statement 3 reads ‘frustrated people are prone to become drug addicts’, how do we come to the simplified conclusion that it’s ‘some frustrated people are drug addict’, a PP statement? . If there are no words (to enable us to come to a PP/UP statement) in the beginning such as this, how do we know whether its UP or PP?
I think none follows because if we say that 1 follows then conclusion will be “some people are not good” whereas there is a statement already given ” some people are good”
Only 2 follows is correct
Statements:
1. Some files are not tubs.
2. All buckets are tubs.
3. Some files are mugs.
Conclusion:
I. Some buckets are files.
II. Some files are not buckets.
III. Some tubs are not mugs.
1) Only I follows
2) Only II follows
3) Only III follows
4) Only II and III follows
5) None follows
Sir, Please solve this.
none follows
only ii follow
there is another method i saw in a video stike out the common terms and then try youll get the answer easily
only 2 and 3 follow
what should we do if in conclusions definitely is given
Statements No Apple is mango
All mangoes are fruits
All fruits are vegetarians
conclusion No Fruit is apple
No vegetarian is apple
some vegetarian are mangoes
some vegetarian are Apple
Answers
None follows
All follows
Either II or IV and III follows
Either II or III and I follow
none of these
Every1 is saying ansr is EITHER II or IV AND III follows
bt m getting only III follows bcz there is no option for this thus NONE OF THESE
PLZ EXPLAIN SM1
Correct Answer EITHER II or IV AND III follows
We get “Either II or IV” by Complimentary Pair Method
When we check Conclusion II “No vegetarian is apple”, we need to use all 3 statements.
From Statement I and II we get “Some Fruits are not Apple”
From this conclusion and III Statement we get ” No conclusion”
Since we get No conclusion and Answers has “Either Or”, We apply Complimentry Method for 2 statement Syllogism
Here Given Either II or IV
1. II and IV has same subjects and Predicate
2.PP+UN pair
So Either II or IV is Correct
and III is also correct (can be solved with normal method)
all follow
Que. Some toys are pen.
Some pens are papers
Some papers are black
Con.stat.
I. Some toys are black
II. No pen is black
III. No toy is black
IV. Some pens are black
Option.
A. Either II or IV
B. Either I or III and either II or IV
C. Either I or IV
D. None of above
bb follows
Sir plz solve above que.
None follows
how to solve possibility cases of syllogism?..i didn’t find them anywhere on your site..these days they ask a lot on possibility cases
A. Some phones are wireless.
B. Some wireless are televisions.
Conclusions:
1. Some phones are televisions.
2. All wireless may be phones.
3. All televisions are wireless.
(a) Only conclusion 1 follows.
(b) Only conclusion 2 follows.
(c) Only conclusion 1 and 2 follows.
(d) Only conclusion 3 follows.
Can anyone pls explain me this
I think correct answer is (b).
2 follows
Can someone answer this question using the above technique!!
Statements:
Some numbers are digits.
No digit is an alphabet.
Some alphabets are letters.
Conclusions:
I. There is a possibility that some alphabets are digits.
II. There is a possibility that some letters are numbers.
1) If only conclusion I follows.
2) If only conclusion II follows.
3) If only conclusion Either I or II follows.
4) If only conclusion Neither I nor II follows.
5) If only both conclusions I and II follow.
can you explain possibility case also
sir you have not explained anything about how to proceed with possibility types syllogism.sir please explain it I am getting too much difficulties at the time of solving.