cracking the gmat 2013 verbal bin 3

This topic has expert replies
User avatar
Master | Next Rank: 500 Posts
Posts: 447
Joined: Sun Apr 22, 2012 7:13 am
Thanked: 46 times
Followed by:13 members
GMAT Score:700

cracking the gmat 2013 verbal bin 3

by hemant_rajput » Wed Jun 05, 2013 6:27 am
A study showed that only ten percent of American dog owners enroll their dogs in formal obedience training classes. More than twenty percent of these dog owners, the study also showed, participate in dog shows. Thus, it is obvious that people who train their dogs are more likely to participate in dog shows than are people who do not train their dogs.

The conclusion above is correct provided which of the following statements is also true?
(A) It is impossible for a dog to compete in a dog show if the dog has not completed at least one formal obedience training class.

(B) The proportion of dog owners who enroll their dogs in formal obedience training classes is representative of the proportion who train their dogs outside such classes.

(C) Dog owners who participate in dog shows only train their dogs by enrolling them in formal obedience training lessons.

(D) Participation in dog shows is a reliable indicator of how much attention a dog owner pays to his dog.

(E) Only purebred dogs can participate in dog shows, so many owners who enroll their dogs in formal obedience training classes are excluded from this activity
I'm no expert, just trying to work on my skills. If I've made any mistakes please bear with me.

Master | Next Rank: 500 Posts
Posts: 341
Joined: Sun Mar 25, 2012 6:59 pm
Thanked: 17 times
Followed by:4 members
GMAT Score:720

by ice_rush » Wed Jun 05, 2013 8:25 am
I was debating between B and C...but I'd go with B. In order to arrive at the conclusion that people who train their dogs are more likely to participate in dog shows than are people who do not train their dogs, we have to consider that a representative sample of people who do not enroll their in obedience training classes in fact train their dogs.


what's the OA?

User avatar
Master | Next Rank: 500 Posts
Posts: 447
Joined: Sun Apr 22, 2012 7:13 am
Thanked: 46 times
Followed by:13 members
GMAT Score:700

by hemant_rajput » Wed Jun 05, 2013 8:43 am
OA:B

Can you please explain the answer numerically ?
I'm no expert, just trying to work on my skills. If I've made any mistakes please bear with me.

GMAT Instructor
Posts: 2630
Joined: Wed Sep 12, 2012 3:32 pm
Location: East Bay all the way
Thanked: 625 times
Followed by:119 members
GMAT Score:780

by Matt@VeritasPrep » Wed Jun 05, 2013 3:43 pm
This is not a well-written (or well thought out) question. The stem isn't correct, as the best answer (B) isn't sufficient to make the conclusion true, just (sort of, kind of, if you're feeling generous) necessary. Let's diagram the argument to see what want in our answer choice:

Premise: 10% of American dog owners enroll their dogs in formal obedience classes.
Premise: 20% of these dog owners participate in dog shows.
Conclusion: People who train their dogs are more likely to participate in dog shows.

The conclusion makes a comparison between dog trainers and dog non-trainers (for lack of a better word), but we don't have any statistics on dog non-trainers! The obvious choice would be something that addresses this, but we don't get it - so we'll take anything that improves our statistics. B says that the training percentage holds for the population, a fact that it is helpful, at least, and gives us a sounder basis of comparison. All the other answers are out of scope or trivial.

This can't be an official question: the logic (and phrasing) is shoddy. I'd advise limiting your exposure to questions like this; just do proper questions from the OG (or if you exhaust those, from retired LSATs, which have well-written CR questions very similar to those on the GMAT).