Two farmers, who never left their farms their whole lives, were lookin

Question

Two farmers, who never left their farms their whole lives, were looking at their dogs and observed that all their border collies were black and white. The border collies were the only things that the farmers ever saw as a mix of black and white. Farmer Gil luckily but correctly observed that if something is a border collie then it must be black and white. Farmer Geva then remarked that if something is not black and white, then it is not a border collie.

The argument is flawed primarily because Farmer Geva:

A. fails to realize that there are other dog breeds apart from border collies

B. fails to realize that being black and white is a necessary but insufficient condition to be called a border collie

C. lacks sufficient information on which to base the condition for being a border collie

D. only observes one type of phenomenon – border collies and their color

E. demonstrates only limited knowledge about the world outside

ManavAgrawal · Answer

My guess is B.
argument : Farmer Geva then remarked that if something is not black and white, then it is not a border collie.

A states that he fails to realise that there other dog breeds, not related to the argument.

B states that geva does not realise it is a necessary but not sufficient condition, this is true geva said, "if not black and white then its not a border collie."

C states lacks sufficient condition on which to base what a border collie is , but passage states that gill noticed correctly the charachterstic of border collie.

D is a distraction, geva only notices color, does not weaken argument as we do not have anyt other facts in the passage

E is a distraction, passage explicitly stated that they have never been outside of their farms

winterschool · Answer

Two farmers, who never left their farms their whole lives, were looking at their dogs and observed that all their border collies were black and white. The border collies were the only things that the farmers ever saw as a mix of black and white. Farmer Gil luckily but correctly observed that if something is a border collie then it must be black and white. Farmer Geva then remarked that if something is not black and white, then it is not a border collie.

The argument is flawed primarily because Farmer Geva:

A. fails to realize that there are other dog breeds apart from border collies  Incorrect

breeding of other dogs is irrelevant

B.  fails to realize that being black and white is a necessary but insufficient condition to be called a border collie   Correct 
 
Geva assume that black and white is the sufficient condition for being a border collie

C. lacks sufficient information on which to base the condition for being a border collie  Incorrect

Geva assume that black and white is sufficient

D. only observes one type of phenomenon – border collies and their color  Incorrect

but this is main point of argument

E. demonstrates only limited knowledge about the world outside  Incorrect

show limited knowledge of similar animal

Bunuel · Answer

OFFICIAL EXPLANATION

Critical Reasoning Questions are all about distractions, so it is crucial to understand how distractors work. Distractors are commonly referred to as trap-answer choices, and their elimination is never automatic.

Consider this question:

Two farmers, who never left their farms their whole lives, were looking at their dogs and observed that all their border collies were black and white. The border collies were the only things that the farmers ever saw as a mix of black and white. Farmer Gil luckily but correctly observed that if something is a border collie then it must be black and white. Farmer Geva then remarked that if something is not black and white, then it is not a border collie.

The argument is flawed primarily because Farmer Geva:

A. fails to realize that there are other dog breeds apart from border collies

B. fails to realize that being black and white is a necessary but insufficient condition to be called a border collie

C. lacks sufficient information on which to base the condition for being a border collie

D. only observes one type of phenomenon – border collies and their color

E. demonstrates only limited knowledge about the world outside

Fairly easily, we can eliminate answers  A, D and E . Answer A is incorrect because it assumes too much – that Farmer Geva is unaware of other breeds. Even if this were true, would this make the argument stronger? Not really, as the argument only needs to deal with one dog breed. Alternatively, choice D criticizes the argument for considering only one phenomenon. However, this is not a flaw as the argument only deals with one type. Finally, answer E can also be easily rejected. It mirrors what the premises already state – that they had never left their farms and knew no other dog types except border collies; therefore, this answer choice does not illustrate the flaw. The toss-up will be between B and C: both answer choices relate to the scope we defined.

At this point we must pause and compare the two answer choices more carefully: The two statements seem similar, but there are differences. According to answer B, going on the information of Farmer Gil that all border collies are black and white, Farmer Geva supposes that this is enough for a border collie to be called as such, wrongly assuming that only color delineates what a border collie is, whereas there may be other conditions which make border collies what they are. Answer C, on the other hand, suggests that Farmer Geva lacks sufficient information to be able to define what a border collie is. Clearly this is not the case – the premises state that Farmer Gil correctly points out that all border collies are black and white and also, as one of the conditions for being a border collie (i.e. being black and white) is a premise, then such factual data is considered correct. Once we isolate this difference, it becomes easier to judge which answer choice is best: Answer C makes a claim that contradicts the premises, whereas answer B correctly indicates a flaw in Farmer Geva’s reasoning.

The correct answer choice is B.

Take home lesson Remember that GMAT questions often yield to the scheme of 3 + 1 + 1. Three relatively easy eliminations, a distractor and a correct answer choice. Find the three quickly, and then pause for a microscopic look at the last two.

Thekingmaker · Answer

Between B and D , orelse B being lengthy addresseseverything hence the answer .....having fun is also really really important in life

SaidNassar1991 · Answer

B is not the answer, it’s a low level question.
B is wrong because:

X => Y
Means negX => negY

Both Farmers, Gil and Geva, are saying the same statement 100%. They are both talking about the necessary condition and not about the sufficient one.

Posted from my mobile device

Ipsmd · Answer

B. fails to realize that being black and white is a necessary but insufficient condition to be called a border collie - wrong

If B&W is a necessary condition, the statement:
"Farmer Geva then remarked that if something is not black and white, then it is not a border collie."
Would not be logically flawed.

Answer C: "C. lacks sufficient information on which to base the condition for being a border collie"
This is correct because it is telling us that Geva does not know that something can have the sufficient conditions to be a border collie and not be B&W, I.e. you can have an albine border collie that satisfies all the conditions to be a border collie. In that case Geva's statement would be flawed.

Posted from my mobile device

DishaAgarwal12 · Answer

I picked B because it read right to me while I was working on this. But after multiple thoughts I feel Geva says nothing but contrapositive of what Gil says which means if Gil is right, then Geva's argument is not flawed. Please help

miag · Answer

Hi,

You are on the right track with your thinking! Let's break it down:
- Gil: If something is a border collie then must be black and white 
- Geva: Not black and white, not border collie.

Gil's logic is a necessary but not sufficient condition to identify border collies. But black and white doesn't uniquely characterizes border collies..

Hope this helps!

DishaAgarwal12 · Answer

But if to be a border collie it must be black and white then geva's conclusion that if it doesn't satisfy a necessary condition then it is not border collie right.

Let's say if you want to pass then you must work hard, hence if i don't work hard i wont pass. does this make sense?

miag · Answer

Hi, 
I understand your point and where you are coming from!

The problem is not Geva’s logic.
 The problem is that Gil’s rule itself is unjustified.

Because Gil inferred a universal rule from  extremely limited evidence :
 
 They only saw  their own  border collies 
 They never left their farms 
 They have no information about border collies elsewhere  
So Gil has  not actually established  that:
 
He has only observed:
 
If someone says:
 
that reasoning would be flawed for the same reason:
 
 limited sample 
 unjustified universal rule  
Hope this helps - let me know!

DishaAgarwal12 · Answer

Hi thanks for the response but this still doesnt solve my doubt as it says "Farmer Gil luckily but correctly observed that if something is a border collie then it must be black and white." So Gil has made the correct judgement

kartickdey · Answer

KarishmaB  please explain this question.I could not understand the official explanation of this question.

AbhishekP220108 · Answer

DishaAgarwal12 , let me try to help.

Think of the situation like this: "If you have an MBA degree, then you must have a grad degree."
As per Gill, without a grad degree, you cannot hold an MBA degree, but having a grad degree guarantees that you are going to have an MBA. No—right, because there are other requirements too, like having a GMAT score, LORs, etc. And Giva just presented the contrapositive. which is the same as gill. The point is, according to Gill, having a grad degree is enough for an MBA. And he didn't consider other factors.

Give it a thought, and if you have any further doubts, do let me know.

DishaAgarwal12 · Answer

But the passage says gill rightly identified?....

KarishmaB · Answer

Wrong question.
Since Gil's argument is said to be correct, Geva's is correct too. She is saying the same thing that Gil is saying.

AbhishekP220108 · Answer

DishaAgarwal12  Yes I totally agree with you Gill has correctly identified the necessary and sufficient condition. Following the same Geva is also technically correct. However, if we look with the context of the argument, Gill and geva both are assuming that border collie and B&W are interchangable. According to them B&W is the only definition for being a Border collie because they have never seen the outer world.

In belief yes the question is poorly worded but still if we look for the overall understanding Gill and Geva who never seen outside their radius they have assumed that if A, then B and so does If B, Then A. They believe that these condition works in both ways.

hr1212 · Answer

I picked C. I do not like this question much because I do not think the reasoning is flawed in the way the options suggest.

Both statements in the passage are true. “If A then B” is logically equivalent to “if not B then not A.”

The only possible issue I see is that Gil based the conclusion on a very limited observation, having only observed their own collies, which happened to be black and white, and then generalized from that.

That said, the question asks about the gap in Greva’s observation, which seems fully aligned with what Gil actually observed. Because of that, I do not think this is a particularly strong question, nor one worth spending too much time on.

Two farmers, who never left their farms their whole lives, were lookin

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