[Reasoning] Logical Connectives (if, unless, either or) for CSAT, CAT shortcuts formulas approach explained « Mrunal

10/07/2013 [Reasoning] Logical Connectives (if, unless, either or) for CSAT, CAT shortcuts formulas approach explained « Mrunal

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[Reasoning] Logical Connectives (if, unless, either or) for CSAT, CAT shortcuts formulas approachexplained

Difference: Syllogism vs Logical connectives

Standard format: logical connectives

Logical connective: if then

Logical connective: Only IF

Logical Connective: UNLESS

Logical connective: otherwise

Logical connective: When, Whenever, every time

Logical Connective: Either OR

Demo Q: Only if: bored TV brother (CSAT 2012)

Demo Q (If, then) Professor Headaches (CAT’98)

Demo Q: Either or: derailed/late train (CAT’97)

Difference: Syllogism vs Logical connectives

Syllogism (all cats are dog) is a common and routinely appearing topic in most of the aptitude exams (Bank PO, LIC, SSC etc). ButLogical connectives is rare. However, in UPSC CSAT 2012 the topic was asked, therefore, you’ve to prepare it.

Syllogism Logical connectives

Contains words like “all, none, some” etc. Can be classified intoUP, UN,PP and PN. Already explained in previous articles.

Contains words like “if, unless, only if, whenever” etc. can beclassified into 1, ~1, 2, ~2 (we’ll see in this article)

Have to mugup more formulas, takes more time than logicalconnective questions.

Less formulas and quicker than syllogism.

Question Statements:

I. All cats are dogsII. some pigs are cats

III. no dogs are bird

Conclusion choices:

A. Some cats are dogsB. No birds are catsC. some pigs are birdsD. Some pigs are not birds

Question statements:

1. I watch TV only if I am bored2. I am never bored when I have my brother’s company.3. Whenever I go to the theatre I take my brother along.

Conclusion choices:

A. If I am bored I watch TVB. If I am bored, I seek my brother’s company.C. If I am not with my brother, than i’ll watch TV.D. If I am not bored I do not watch TV.

Standard format: logical connectives

If, unless, only if, whenever, every time etc. are examples of Logical connectives.Whenever you’re given a question statement, first rule is: question statement must be in the standard format.The standard format is****some logical connective word *** simple statement#1, simple statement #2.It means, the question statement must start with a logical connective word, otherwise exchange position. For example

Given question statement Exchange position?

If you’re in the army, you’ve to wearuniform

no need because the simple statement containing “IF” is given in the beginning. Thisis already in the standard format.

You’ve to wear uniform, if you’re in thearmy

We need to exchange position because the part containing “IF” is not given in thebeginning of this statement, given statement is not in standard format.Therefore, Rewrite given statement asIf you’re in the army, you’ve to wear uniform.

Need to exchange position. Because statement doesn’t start with the logical

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You’ve to salute, wheneverCommanding Officer comes in yourcabin.

connective “whenever”.Therefore rewrite the given statement asWhenever CO comes in your cabin, you have to salute.

Now let’s derive valid inferences for various logical connectives.

Logical connective: if then

Consider these two simple statements

1. You’re in army2. You’ve to wear uniform.

These are two simple statements. Now I’ll combine these two simple statements (#1 and #2) to form a complex statement.

If you’re in army(#1), you have to wear uniform.(#2)

What about its reverse?

You’ve wearing uniform (#2)—> that means you’re in the army.(#1)But there is possibility, you’re in navy—-> you’ll still have to wear a uniform. It means,if 1=>2, then 2=>1 is not always a valid inference.Let’s list all such scenarios in a table.

Given statement:

If you’re in army(#1), you have to wear uniform.(#2)

Inference? Valid / invalid?

1. If #2, then #1If you’ve to wear uniform, you’re inarmy.

you’ve to wear uniform in navy, air force, BSF etc. so thisinference is not always valid.

2. If not #1, thennot #2

if you’re not in army, you don’t have towear uniform.

you’ve to wear uniform in navy, air force, BSF etc. so thisinference is not always valid.

3. if not #2, thennot #1

If you don’t have to wear uniform,you’re not in army.

Always valid.

In the exam, you don’t have to think t̂hat much. Just mugup the following rule:Given statement =“If #1 then #2”, in such situation the only valid inference is “if Not #2, then not #1”.

In other words, “if 1st happens then 2nd happens”, in such situation, the only valid inference is “if 2nd did not happen then 1st didnot happen”.Now I want to construct a short and sweet reference table for the logical connective problems. So I’ll use the symbol ~=negative.

~1=meaning NOT 1 ( or in other words, negative of #1)

Given Valid inference

If 1, then 2 If not 2, then not 1

If 1=>2 ~2=>~1

In some books, material, sites, you’ll find these rules explained as using “P” and “Q” instead of 1 and 2.But in our method, you first make sure the given (complex) statement starts with a logical connective (or you exchange position asexplained earlier)We denote the first simple sentence as #1 and second simple sentence as #2.The reason for using 1 and 2= makes things less complicated and easier to mugup.

Logical connective: Only IF

In such scenario, you’ve to rephrase given statement into “if then” and then apply the logical connective rule for “if then”.For example: given statement: he scores a century, only if the match is fixed.The “standard format”= only if the match is fixed(1), he scores a century(2).In case of “only if”, we further convert it into an “if” statement, by exchanging positions. That is



if he scores a century(#2), the match is fixed(#1).Then apply the formula for “if then” and get valid inference.Here we’ve “if 2=>1” as per our formula for “if then”, the valid inference will be ~1=>~2. Don’t confuse between 1 and 2.Because essentially the valid inference is “negative of end part => negative of starting part”.Therefore “if 2=>1 then ~1=~2”similarly “if 98=>97, then valid inference will be ~97=>~98”Similarly “if p=>q, then valid inference will be ~q=>~p”,similarly “if b=>a, then valid inference will be ~a=~b”) .Update our table

Logical connective Given statement Valid inference using symbol Valid inf. In words

If If 1=>2 ~2=>~1 Negative of end part=> negative of start part

Only if Only if 1=>2 ~1=>~2 Negative of start part=>negative of end part.

Logical Connective: UNLESS

Given statement: Unless you bribe the minister(#1), you will not get the 2G license.(#2)Unless = if…..not.So, I can re-write the given statement as(new) Given statement: If you don’t bribe the minister(#1), you’ll not get the 2G license.(#2)

How to come up with a valid inference here?

#1 You don’t bribe the minister

#2 You’ll not get the 2G license.

For “if..then”, We’ve mugged up the rule: 1=>2 then only valid inference is ~2=>~1. (in other words, negative of end part =>negative of starting part).let’s construct the valid inference for this 2G minister.we want ~2 => ~1Negative of (2) => negative of (1)Negative of (you’ll not get the 2G license)=>negative of (you don’t bribe the minister)You’ll get the 2G license => you bribe the minister.In other words, If I see a 2G license in your hand, then I can infer that you had definitely bribed the minister.This is one way of doing “unless” questions = via converting it into “if…not” type of statement.The short cut is to mugup another formula: unless1=>2 then ~2=>1.How did we come up with above formula?

Deriving the formula for unless

Unless 1=>2 (given statement)if not 1=>2 (because unless=if not)if ~1=>2 (I’m using symbol ~ instead of “not”)~2=> ~(~1) (because we already mugged up the rule “if 1=>2, then valid inference is ~2=>~1)~2=>1 (because ~(~1) means double negative and double negative is positive hence ~(~1)=1)

This is our second rule: Unless1=>2 then ~2=>1

Table


If If 1=>2 ~2=>~1 Negative of end part=> negative of start part


Unless Unless 1=>2 ~2=>1 Negative of end part=>start part unchanged.

Logical connective: otherwise

Suppose given statement is: 1, otherwise 2.you can write it as unless 1 then 2. (unless1=>2)Then use the formula for “unless.”

Logical connective: When, Whenever, every time

Given statement: he scores century, when match is fixed.This is not in standard format of “**logical connective word**, simple statement #1, simple statement #2.”So first I need to exchange the positions: “when match is fixed (#1), he scores century (#2)”.



In case of when and whenever, the valid inference is= same like “If, then”. That means negative of end part=>negative of startingpart.Same formula works for “whenever” and “Everytime”.Update the table


If If 1=>2

~2=~1 Negative of end part=> negative of starting partWhen When 1=>2

Whenever Whenever 1=>2

Everytime Everytime 1=>2


Unless Unless 1=>2 ~2=>1 Negative of end part=>starting part unchanged.

Logical Connective: Either OR

Given statement: Either he is drunk(1) or he is ill(2).

In such cases, if not 1 then 2. And if not 2 then 1.

Meaning,

1. if he is not drunk then he is definitely ill2. if he is not ill, then he is definitely drunk

both are valid. Update the table

Logicalconnective

Given statementValid inference usingsymbol

Valid inf. In words

If If 1=>2

~2=~1 Negative of end part=> negative of starting partWhen When 1=>2

Whenever Whenever 1=>2

Everytime Everytime 1=>2


Unless Unless 1=>2

~2=>1 Negative of end part=>starting part unchanged.Otherwise

1 otherwise 2=> rewrite asUnless1=>2.

Either or Either 1 or 2~2=>1~1=>2

Negative of any one part=> remaining part remainsunchanged.

Now let’s solve some questions from old CSAT and CAT papersPlease note: in the exam, actual wording / meaning of the simple statement doesn’t matter. Just apply the formulas as given inabove table.

For example, “if you’re in army, you have to wear uniform.” Then valid inference is ~2=>~1 (you don’t have to wear uniform,then you’re not in army).Now ofcourse there would be exceptional situation when army officer/jawan doesn’t need to wear uniform, for example duringespionage mission behind the enemy lines. In that case you don’t have to wear uniform, but you’re still in the army.But keep in mind, while solving logical connective question under the “aptitude/reasoning” portion you don’t have to surgicallydissect or nitpick the meaning every statement. Just “if 1=>2” then “~2=>~1”.

Demo Q: Only if: bored TV brother (CSAT 2012)

Examine the following statements:

1. I watch TV only if I am bored2. I am never bored when I have my brother’s company.3. Whenever I go to the theatre I take my brother along.

Which one of the following conclusions is valid in the context of the above statements?



A. If I am bored I watch TVB. If I am bored, I seek my brother’s company.C. If I am not with my brother, then I’ll watch TV.D. If I am not bored I do not watch TV.

Approach

First we’ll construct valid inferences from the question statements

Given Question Statement #1:

Given =I watch TV only if I am boredThis is not in standard format. So first exchange positionOnly if I’m bored (1), I watch TV(2)What is the valid inference? Just look at the formula tableOnly if 1=>2 then ~1=~2Valid inference= if I’m not bored, I do not watch TV.Look at the statements given in the answer choices, (D) matches. Therefore, final answer is (D).

Demo Q (If, then) Professor Headaches (CAT’98)

You’re given a statement, followed by four statements labeled A to D. Choose the ordered pair of statements where the first statementimplies the second and two statements are logically consistent with the main statement.

Given statement: If I talk to my professors(1), then I didn’t need to take a pill for headache.(2)

Four Statements

A. I talked to my professorsB. I did not need to take a pill for headacheC. I needed to take a pill for headacheD. I did not talk to my professor.

Answer choices

I. ABII. DC

III. CDIV. AB and CD

Approach

Given statement is in standard format already

#1 I talk to my professors

#2 I didn’t need to take a pill for headache.

Let’s classify the four statements

Classification Four statements

1 A. I talked to my professors

2 B. I did not need to take a pill for headache

~2 C. I needed to take a pill for headache

~1 D. I did not talk to my professor.

Answer choice (i) AB

If you observe the answer choice (I): AB= I talked to my professors, I did not need to take a pill for headache. This is valid because if1=>2 is already given in the question statement itself.

Answer choice (ii) DC



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I did not talk to my professor (~1), I needed to take a pill for headache (~2). Meaning ~1=>~2.This is invalid because as per our table, if 1=>2, then valid inference is ~2=>~1.

Answer choice (iii) CD

I needed to take pill for headache (~2), I did not talk to my professor (~1). Meaning ~2=>~1. This is valid as per our table. Thereforefinal answer is (IV) AB and CD

Demo Q: Either or: derailed/late train (CAT’97)

Given statement: either the train is late (1) or it has derailed (2)

Four statements

A. Train is late = 1B. Train is not late = ~1C. Train is derailed =2D. Train is not derailed =~2

(^note: I’ve classified the statements in advance)

Answer choice

I. ABII. DB

III. CAIV. BC

Approach

As per our table, the valid inferences for either or are

~2=>1 If the train is not derailed, it is late. DA

~1=>2 If the train is not late, it is derailed BC

Correct answer is (III): BCFor more articles on reasoning and aptitude, visit Mrunal.org/aptitude

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180 comments to [Reasoning] Logical Connectives (if, unless, either or) for CSAT, CAT shortcuts

formulas approach explained

« Older Comments 1 2



VengateshReply to this comment

Sir thank you very much

gauravReply to this comment

mrunal sir what wil we do if word DESPITE comes..plz reply

CARMReply to this comment

Thanks Mrunalin ur article….last line should beCorrect Ans is IV BCAnywaysCan u help me with this

1)The aircraft takes off if the light blinks2)Only if there is no storm the aircraft takes off3)If there is a storm the light does blink

optionsa. if the light blinks there is no stormb. the aircraft takes off if there is no storm

Solutionstorm==>not take off===>not blinkblink ===>no storm====>…….

here cant we add “take off” which will make option b also true.(can see option a is true)if not why cant we do thatPlz answer!!!!

shaniReply to this comment

option A cannt be correct3)If there is a storm(1) the light does blink(2)n as per rules-(2)=>-(1) 0r (1)=>(2)and a. if the light blinks there is no stormthis is contradictory

neelimaReply to this comment

shani ji here both statements a & b are wrong na

love shandilyaReply to this comment

yupp both r wrng

KritikaReply to this comment

Statement B is correct. It is rephrase of given statement “Only if there is no storm the aircraft takes off” -> The aircraft takesoff (only) if there is no storm.


what is wrong in option b??

http://mrunal.org/2013/04/reasoning-logical-connectives-if-unless-either-or-for-csat-cat-shortcuts-formulas-approach-explained.html?replytocom=53644#respond










Aditya_S8Reply to this comment

sir post some practice questions too or refer to some book from where we may get some good questions 4 practice.

freakReply to this comment

First time i understand these thing in a very lucid manner…..thanks to u mrunal!!!!

freakReply to this comment

thanks u mrunal

manojReply to this comment

thank you so much !! you are really a true teacher or much more then that….awesome explanation man !!

ganesh guptaReply to this comment

Sir u are great, u explain tough things with ease. I like all your articles. U are a great teacher. U are doing a great job, God has to bless u.

helpReply to this comment

Dear Mrunal, how many months of study is necessary to clear upsc cse to become an IAS or IPS ? Thank you.

AlokReply to this comment

Hi Mrunalthanks a lot for all ur helpCan u please give some explanation on type of Syllogism questions where we have to find which of statements are “both can be true but bothcannot be false ” or ” both can be false but cannot be true” or ” both can be true and both can be false”Pls throw some light on this kind of questions , it was asked in 2011 paper

AnuragReply to this comment

Pl help me with following quesWhen ever shyam hears of an exam, he losses sleepa) shyam heard of an examb) shyam didnt heard of an examc) shyam lost sleppd) shyam didnt lost losse sleepOption –1) CA2) BD3) DB4) ADAns according to TMH is – 1,


CA cnnt be answer as per rulesWhen ever shyam hears of an exam(1), he losses sleep(2)so as per rules-(2)=>-(1) OR (1)=>(2) n CA IS contradictory so it cnnt be

amitReply to this comment













ansr= DB ~2=>~1

truptiReply to this comment

ans DB

monuReply to this comment

please apply ur mind… don’t blindly belief on any guide………… or material. answer is (DB)

diwasReply to this comment

ans is DB

AnuragReply to this comment

Another question

when i see horror movie i had a bad dreama) i saw a horror movieb) i didnt saw a horroe moviec) i didnt had a bad dreamd) i had a bad dream

option :1) CB2)AD3) BC4) AC

Answer According to TMH – a, but m confused b/w option 1 & 2


yupp both r ryt

amitReply to this comment

ansr CB ~2=>~1 ,,v hv to mk inference. 2nd option is just qusn statemnt but if in ansr they gv both ,,,tick both oderws CB.

anuragReply to this comment

Thanks Amit

zeenat samimReply to this comment

restatement is never a valid answer, its neither a conclusion nor a reason.

GauravReply to this comment

@anurag……. option 3 in sleep wala ques.N both 1 n 2 are correct in bad dream ques.

anuragReply to this comment













Thanks Gaurav

PRAKAH K SReply to this comment

Hello Sir thanks a lot for simplifying sylloligism. Sir, Somewhere in ur blog u mentioned abt tool which remove unwanted texts before takingprintout, so that it will save lot of pages. could you please mention abt tht tool so tht we can save no of pages and also money :-) while takingprintout.

jReply to this comment

@parthi

Basically if we make the venn diagram of both the options they would be same. I guess this seems like a bug with with venn diagram method.Well, but wat seems more appropraite is if rivers flows c cranks and not the other way round as see…If A then B cannot be stated as only if B then A when i guess their Venn diagrams would be identical. Let me know!

SUMIT KARELIReply to this comment

Thanks a lot….

jReply to this comment

Wat do we infer from ” all except a few” some are and simultaneously some are not?

AmitReply to this comment

Please help…1)some who study will not become graduates.2)To become graduates student must study.3) Only students can become graduates.

conclusion:-a)Some who become graduates are not student.b)All students who study become graduates.c)Some who study and become graduates are students.d)Students who do not study will not graduate.

मन ुझाReply to this comment

C & D can be concluded becuase the statement 2 says To become Graduates students MUST study. and 3rd says that only Studentscan become Graduates.In Mathematics-That means Graduate is a subset of Study and Student both andStudy is a subset of Student.so there are 3 concentric circles with Student the outer most, then Study and the inneromst circle is Graduate.

In simple words (i m trying)-A) Graduates are students first,grads second Why ? because state 3 says ONLY studs can become Grads. Hence this cant beconcluded.B) All students who study cant be sure that they will DEF Graduate (just as 17lakh applicants gave SBI but only 1500 will be selected),anyways, because Statement1 says Some who study still not Graduate. Hence this cant be concluded.C) Since the 3rd statement says , that whosover is Grad he is a Student too and State 2 says that Stud must have studied to becomeGrad. Hence this can be concluded.D) Students who dont study = Can never Graduate. Why ? Because st2 says They MUST study but its not necessary that they willDEFINITELY graduate. but they stand a chance. Hence this can be concluded.

I hope it helps. Do tell the Answer too.

vikkyReply to this comment

Except “A” other conclusions r correct. 3 concentric circles ll not come. Please check. B can be concluded as second statement










says “2)To become graduates student must study.”. so students if they study ll become graduate. (SBI s a competitive xam so allwill not clear, but any student can become graduate provided he studies. NOTE :Even i am a graduate =D )..


Vikky

HKReply to this comment

i dont think C can be concluded because

Only Students = Graduates (and no other)quantifier in C is “some” it has to be “ALL”Lets say i am doctor and i studyif i become graduate i must have been Student. so not some but All

ans is D

ANSWER??


Your point is correct but here its not that Statement cant be concluded.

Whenever its given –

“All Roads are infrastructure.”

Then you can always conclude that – “Some Roads are infrastructure.”Its not necessary that if ALL is given then the conclusion must have all. It can obviously have “SOME” .

HKReply to this comment

i disagree,

All roads are infra. subject is distributed.. its not logically correct to blur the space boundarythough true in common sense

some roads are infra cant be “concluded” because in this statement neither subject nor object is distributed..

as roads is Subset of infra we can say that some infra is roads. it not a conclusion too because its an INVERSE

BHAI JISNE POOCHA HAI QUESTION WOH ANSWER TO BTA DOOOO…….

k

I think it is C and D both. And the explaination of manu jha is correct. pls correct answer?

naina agarwalReply to this comment

sir, in question..you can see the star only if you go to cinema…correct answer should be i didnt see the star i didn’t go to cinema..bt reverseis givn…please help me with this thnku…

naina agarwalReply to this comment

i got the solution..thnku..

Tej BharathReply to this comment

You are the king,, mrunal…










zeenat samimReply to this comment

mrunal, can i infer from your explanation of “either – or” type-that answer format will be :--1(negative of first part)and 2(unchanged second part)?????

pramodReply to this comment

Sir, it is very interesting and very good elaboration. i read a book of CAT (author name started by a. not mentioning full name). but there idoes not find the same thing as u wrote . thanks ………..

anil bishnoiReply to this comment

thanx for the explanation…it will be nice if u elaborate on more interconnected sentence fore.g If ankita eats pastry, then it is a black forest or a pineapple.

plz xplain all the possible outcome.

durga prasadReply to this comment

hello Admin,I am new to this site. For the info above discussed there are other valid outcomes as well.Only if 1=> 2 it also mean 2=>1 apart from ~1=>~2. Please confirm it.

Kulvinder ruhilReply to this comment

Dear Mrunal Sir,Your methods to derive conclusions only in negatives like not 1 not 2 types .I faced a lot of problem while facing questions based on non negative conclusion.One more doubt Can I derive another conclusion based ontwo already derive conclusions.Q.11.He writes whenever he is angry.2.It is cloudy only if he is angry.3.He is angry only if he is hungry.ConclusionA.He writes whenever he is hungry.B.He is hungry if he writes.C.He writes only if it is cloudy.D.Whenever it is cloudy,he writes.Q-21.There are as many engineers in this organisation as there are doctors.2.Only if a doctor agrees to a plan will an engineer agree to plan.3.An engineer agrres to a plan only if the majority of engineers including him agree to it.ConclusionsA.Only if an engineer agree to a plan will a doctor agree to it.B.An engineer will agree to plan if all doctor agree to it.C.An engineer might agree to a plan if the total number of engineers agreeing to a plan is more than half the total numbers of doctors.D.If all doctors agree to a plan,all engineers agree to it as well.

Reply asap.

Ravi PrasadReply to this comment

Hello Siralthough option D)If I am not bored I do not watch TV. (csat 2012)can definitely be concluded.why not optionB)If I am bored, I seek my brother’s company.bcoz I am bored = negative of ( i am not bored) alsoI SEEK my brother company = does not SEEK here mean that HE IS NOTIN HIS BROTHER’S COMPANY.









IF AM WRONG PLEASE CORRECT….

pritiReply to this comment

i really appreciate ur contribution for us sir .every time i read ur article i just say -u r really too good and in my view best tr .

aditiReply to this comment

Hw can i Solve ths:::

You cannot clear the CSAT unless you are intelligent1 u r intelligent2u can clear the CSAT3 u r nt intelligent4 u cannot clear the CSAT

answer is :: C……….. How???? Plz help me!!

nishatReply to this comment

tell us all the options first.how do we know what is A , B, C and D?

aditiReply to this comment

thnx for reply…You cannot clear the CSAT unless you are intelligenta u r intelligentb u can clear the CSATc u r nt intelligentd u cannot clear the CSAT

conclusion: are bd, ac, cd, ab, ; given ans is cd, how? accordingly above, valid interference is ~2=>1, ~2 cancels negativesentence ; is m right????

plz

vipsReply to this comment

look…it means if u cleared the csat, u r intelligent….ie all csat are intelligent….draw a venn with intelligent encircling csat andu get ur answer…not intelligent means no csat,,,,

love shandilyaReply to this comment

luk aditiYou cannot clear the CSAT unless you are intelligentU CAN WRITE DYS ASunless you are intelligent,You cannot clear the CSATNOW ABOVE SENTENCE CAN BE WRITTEN IN D FRM LYK DATUNLESS => IF…NOTso …….if you r nt intellignt ,u cannot clear CSATNOW SIMPLY APPLY D LOGIC OF IF NOT2 SOLUTIONS R POSSIBLERULE A…~2=~1RULE B…1=2SO WE WILL;TOOK CD as a answer by applyn RULE Bon d other syd other options not CRRCTHOPE U UNDRSTND D SOLUTION

subramaniyanReply to this comment










Dear sir,Whether in the last example ,AD and DA are both possible. Please enlighten us :)

amalReply to this comment

damn good man..

sunny vermaReply to this comment

Sir,How to solve a question which do not contain any “if” and “only if”. Below is the question asked in CL test series:

Statement: There are as many engineer in the organization as there are doctors.


another question which i am unable to solve is following:

statements are:1. whenever prices goes up , farmers are affected2. Farmers are affected only if it does not rain3. It rains if there are cloudsWhich of the following conclusion can be drawn:a) Farmers are always affected by rains,b) If it does not rain Farmers are affectedc) Whenever there are clouds prices go upd) If there are clouds farmers are not affected

Correct Answer is D, But how and how to solve option A?

RKSReply to this comment

1) Prices up —-> Farmers affected (FA)2) NO rain —–> FA3) Clouds —-> Rains

So,OP 1) Does not qualify as —- FA by Price rise alsoOP 2) Does not qualify as —- FA by Price rise alsoOP 3) No relation between the threeOP 4) Correct – coz CLOUDS —-> Rains —-> Farmers NOT affected.

Hope this helps.

thanks


Thanks for your reply but kindly explains below related queries:1. as per universal rule.. only if p then q : q->p && ~p->~q so deduction of statement 2 ["Farmers are affected only if it does not rain"]would be as followsFA -> No rain && Rain->no FA

but you have derived it as ” 2) NO rain —–> FA “… HOW??


pretty easy mate…… u can solve simply by logic… statement 2 is antithema of conclusion 1,,,more systematic approach…1. price imples farmers affection ie all prices are farmers… 2 //farmers implies no rain…3 cloud imples rainthat all cloud are rain…now draw venn with prices encircled by farmers in turn encircled by no rain and separate circle of cloud u get ur answer











ask any csat question… can ask gs as well

dark funtazyReply to this comment

question -if P runs for president, C does not.answers 1.P runs for president,C does not.2.C runs for president,P does not.3.both P and C run for president.4.neither P nor C run for president.which of the above 4 statements are correct.

dark funtazyReply to this comment

question -if P runs for president, C does not.answers 1.P runs for president,C does not.2.C runs for president,P does not.3.both P and C run for president.4.neither P nor C run for president.which of the above 4 statements are correct.

PRAVEENReply to this comment

SUPERB EXPLAINATION……. YET NEED OF SOME MORE EXAMPLES TO SOLVE N PRACTICE SR

NawinReply to this comment

dedicated to you ” http://www.youtube.com/watch?v=vwsKWiXlA78 ” .. u have made a difference

ShibprasadReply to this comment

for Unless, is it ~ 2=> 1 or ~2=>~1 , please clarify

ShibprasadReply to this comment

sorry got it, thanks

sumitReply to this comment

hi sir want to prepare for the post of probationary officer and rbi grade b officer so please suggest me the best practise paper and alsoeconomics and banking terms…its my humble request to u and thanking you

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[Reasoning] Logical Connectives (if, unless, either or) for CSAT, CAT shortcuts formulas approach explained « Mrunal