reg this CR

[ashwinkumar96mba]

Each bank in the town of La Rinconada has only a single set of locking doors at its entrance. In the town of Inverness, on the other hand, the entrances to nearly all banks are equipped with two sets of locking doors, operated by a mechanism that allows only one set of doors to be open at a time. It is clear, then, that banks in Inverness experience more robbery attempts than do those in La Rinconada, and have thus adopted the extra doors as a security measure.

Which of the following, if true, most weakens the argument above?

a) Last year the number of bank robberies in La Rinconada was almost one-half greater than the corresponding figure for the previous year.
b) Inverness is known for its harsh winters, while the climate of La Rinconada is quite temperate year-round.
c) The mechanism of the double doors used by banks in Inverness allows bank security personnel to lock the doors remotely.
d) Bank robbery attempts are typically unsuccessful, and, even when the robbers do manage to escape with stolen money, the sum is usually quite small.
e) Inverness has almost twice as many police officers per capita as does La Rinconada.


I chose C but the correct answer is B. I understood that I have to give an alternate reason to weaken the argument. C is effectively doing that. How is B the right answer?

[arnabgangully]

There are more robbery attempts for the Inverness Banks and this is the reason that they have applied more security i.e. double door set security.

So the issue needs to be resolved for more attempts >>> Anything which weakeans then situation where like awkward weather conditions prohibits robbers to rob is weakening the argument in this context so B is The right choice no other choice is matching with this situation.

[tim]

Arnab, your analysis is fundamentally flawed because you are assuming the conclusion you are trying to weaken. It's also a stretch to assume that bad weather causes fewer robbery attempts..

The real problem with C is that it does nothing to strengthen or weaken the argument. B is correct because it provides an alternate explanation for why there are two sets of locking doors other than as a measure to reduce attempted robberies..

[pec.harchetan]

Dear Tim

I agree that B is giving alternate application of two sets of locking door, but this option is forcing us to think beyond the premises of the passage. There is no information that locking doors are bad conductor of heat.

I may be wrong in my assumption that we are not required to think out of the premises. But if you have any GMAT question (as an example) of similar type, please share.

Even C is saying that may be those banks are more technically advanced which have facility to use remote controls for their doors. How can we only relate this to the security of the bank.

I request for your reply.

[tim]

it turns out that anytime you are supplying an assumption or trying to strengthen or weaken the conclusion, you MUST include something that goes beyond the premises. that's the nature of the assumption family of questions. if you did not go beyond the premises of the argument, you would not be supplying an assumption or information that would strengthen or weaken the argument..

[georgepaul0071987]

Can we eliminate (C) for these reasons ?

1)It simply mentions what the situation is for Inverness but does not explain the corresponding situation for La Rinconada.

For instance this option doesn't say that "The double door mechanism allows security personnel to lock the doors remotely but the single door mechanism doesn't allow the security personnel to lock the doors remotely "

Since we are comparing two situations here we do need both sides of the comparison right ?

2)Option C simply says that the double door mechanism allows the security personnel to lock the doors remotely , it doesn't mention this as an advantage for it to be considered relevant here .

[jnelson0612]

I like to break down arguments this way:
Conclusion: the doors in the banks in I are there as a security measure

WHY?
Premise: LR banks have only a single set of doors. I banks have a double set of doors in which only one door can open at a time. I has had more robbery attempts than LR has.

What is the author assuming? That the only reason that would explain the difference in doors is the robbery attempts.

To weaken this argument we directly challenge this assumption by offering another explanation. This is what answer choice B does.

I think that C) strengthens the idea that the reason for the double-doors is security. It gives us an additional security benefit to the double doors.

[maxschauss]

b) Inverness is known for its harsh winters, while the climate of La Rinconada is quite temperate year-round.

I don't get why this is related to the argument. It does NOT AT ALL give an alternate explanation, it just has nothing to do with the argument. I could also say "My mom baked a cake yesterday.", it would be the same. If the answer choice would be something like "blabla to protect against harsh weather conditions.", then okay. But the the simple statement B is just ****!

[tim]

This problem has been explained rather thoroughly in the thread. If you don't like the official answer to a question, the appropriate response is to figure out how to make it make sense in your mind, not to write an angry post that suggests there is something wrong with the problem. You will encounter far more success on the GMAT if you learn to understand why the right answers are right and the wrong answers are wrong than if you simply argue about the questions. The GMAT never awarded anyone points for disagreeing with them.. :)

[StaceyKoprince]

I agree with Tim that, sometimes, we just have to suck it up. I can't tell you the number of times I've wanted to argue with an official question. :) But my only real option is to figure out how THEY think / write questions / do things and respond accordingly.

We have so many "one little piece" posts here that I want to take a crack at laying out everything in one post:

Step 1: Q type = weaken

Step 2: deconstruct arg

LR Bs: 1 d
I Bs: 2d, one open at time
Intermed Concl: I more robb than LR
Final Concl: I uses 2d for security (as a result)

Step 3: State the Goal
On weaken Qs, we need something that makes the conclusion a little bit less likely to be true or valid. The correct answer will introduce something new, but that something new will address some assumption in the original argument.

So I want something that will make it at least a little less likely that I decided to use 2d specifically for security purposes or in response to the idea that there are more robberies.

What's the author assuming? He's assuming there actually are more robberies in I. He's assuming there isn't some other reason for using the 2d system, a reason that has nothing to do with security.

Step 4: Answer choices

(A) Only gives me figures for LR; tells me nothing about I. The conclusion is about I, so this neither strengthens or weakens the C.

(B) This offers an alternate reason to have a 2-door system where only one door opens at a time - it helps keep some of the cold air out in I, which isn't an issue in LR. If this is true, then it somewhat weakens the idea that I MUST have the 2-door system specifically in order to increase security (because there is now a possibility that the weather reason is the only reason they have the 2-door system).

(C) Locking the doors remotely is an improvement in security. If I uses this system in order to improve security, then that reinforces (strengthens) the conclusion.

(D) Doesn't address why I has a 2-door system, which is the heart of the conclusion.

(E) Doesn't address why I has a 2-door system, which is the heart of the conclusion.

Correct answer is B. It addresses one of the 2 assumptions that I brainstormed before looking at the answers: the author assumes that there is not an alternate reason why the banks would have these 2d systems.

Note: one of the objections above was that the (correct) answer didn't specifically spell out that the 2d system would protect against those harsh weather conditions. On strengthen / weaken questions, it isn't necessary to spell it out completely. It's only necessary to introduce something that COULD be an alternate explanation. If it is true that this harsh weather exists in I, then that could be one possible justification for the 2d system. And if that is a possible justification, then the guy's argument just got a little bit weaker. I could say, well, hey, wait a minute - how do you know that this MUST be because of security? Maybe it's just because the weather is so much colder in I. You haven't even given me any evidence that there are more bank robberies in I - you're just assuming it!

p.s. If you ever want to see these 2-door systems in use, come visit me in Montreal, where the temperature is currently a balmy 6 degrees fahrenheit. :) We all have them, even in our homes.

p.p.s. Though I did not write this question, something similar did actually happen to me once. A visiting relative thought that there must be serious security issues because all storefronts (including banks) had these double doors - was it to slow down / hinder robbers? I gently explained that it was because of winter. :) (It was summer at the time, so the reason for having this set-up was very out-of-sight, out-of-mind.)

[Yylevin90]

im from california where ive never seen double doors to keep out the cold air how should i have known this. GMAT test makers cant assume we all live in cold climate places. or should i have gotten the answer by POI

[tim]

I don’t know what POI is, but you should definitely have "known this" not because of any prior knowledge you have but because the question brings it up directly as a possibility. In this problem, you’re looking for ANYTHING that could explain the double doors other than a crime deterrent. When B tells you they have cold weather, your thought should be "I’m from California and I have never seen double doors to keep out the cold, but is it POSSIBLE that this could be the reason for the double doors?" And then your answer of course should be "yes"! :)

[anu_john_28]

I chose C thinking that it provided an alternate explanation ..namely operational convenience..

[RonPurewal]

I chose C thinking that it provided an alternate explanation ..namely operational convenience..

* First, choice C doesn't differentiate between La Rinconada and Inverness. We're not just looking for a reason to have the doors; we're looking for a reason to have the doors in Inverness, but not in La Rinconada.

* Second, choice C mentions, specifically, that the system allows security personnel to lock the doors.
The primary purpose of security personnel is crime prevention, not "convenience". So, in this sentence, choice C is actually additional evidence that there is a crime-related issue in play.

[sunny.singh25]

I can appreciate the logic proffered by the experts as regards option B. However, I would request a reconsideration of option C.
Ron, to say that the primary purpose of security personnel is crime prevention and not convenience is also to assume it. It may come as a surprise, but in the place I belong to, security personnel (although usually only a solitary person with a poor gun!) in most banks double up as gate-men, with an additional task of facilitating ingress and egress of customers. GMAT, being a truly global test, should really not put questions whose answers require students to draw on their social experiences, as these experiences may be wholly different for people across societies. Therefore as suggested earlier, even the argument of using such a system to keep out cold air is also alien to many.
Thus, I am tempted to consider choice C, as I agree with the objective idea of looking at the remote control facility as something allowing for easy operation of the doors in case of a two-door system as compared to a single-locking door. This could offer an alternate explanation for its use only as a security measure and suggest that the remote controlled double-door system with its easy operational use even from a distance, could have prompted banks in Inverness to employ it.