Maria won this year’s local sailboat race by beating Sue, the winner

Question

Maria won this year’s local sailboat race by beating Sue, the winner in each of the four previous years. We can conclude from this that Maria trained hard.

The conclusion follows logically if which one of the following is assumed?

(A) Sue did not train as hard as Maria trained.

(B) If Maria trained hard, she would win the sailboat race.

(C) Maria could beat a four-time winner only if she trained hard.

(D) If Sue trained hard, she would win the sailboat race.

(E) Sue is usually a faster sailboat racer than Maria.

semwal · Accepted Answer

Maria won this year’s local sailboat race by beating Sue, the winner in each of the four previous years. We can conclude from this that Maria trained hard. 
The conclusion follows logically if which one of the following is assumed?

This is a CAUSAL RELATIONSHIP----- 
Assumptions-  Training hard ONLY led to Maria's win.......
 Nothing else led to Maria's win

(A) Sue did not train as hard as Maria trained.... cant say what applies for Sue... we only know what applies for Maria . 
(B) If Maria trained hard, she would win the sailboat race..... cant say about future..... this time she won because she trained hard...WOULD does not invoke a total sence of certainty.... . 
(C) Maria could beat a four-time winner  only if  she trained hard..... ....  Training hard ONLY led to Maria's win.......
 Nothing else led to Maria's win.....correct  
(D) If Sue trained hard, she would win the sailboat race..... .. cant say what applies for Sue... we only know what applies for Maria . 
(E) Sue is usually a faster sailboat racer than Maria....... not an assumption .

IMO "C"...............

KUDOS IF YOU PLEASE............

anairamitch1804 · Answer

Now let's look at B vs C.

B) If Maria trained hard, she would win the race.

Does this prove that Maria MUST HAVE trained hard? No - just because training hard is one way to win the race doesn't mean that it's the ONLY way to win the race. For example, maybe Sue broke her leg at the starting line. Since (B) doesn't eliminate other possible paths to victory, it doesn't PROVE the conclusion.

C) Maria could beat a four-time winner ONLY IF she trained hard.

Well, we know that Maria beat Sue, a four-time winner. If we add in a new piece of evidence that the ONLY WAY to do so is to train hard, then it MUST BE TRUE that Maria trained hard. Accordingly, (C) proves the conclusion.

Bunuel · Answer

OFFICIAL EXPLANATION

The structure of the argument is:

Premise:  Maria won this year’s local sailboat race by beating Sue, the winner in each of the four previous years. 
 Conclusion:  We can conclude from this that Maria trained hard. A quick glance at the argument reveals a gap between the premise and conclusion—winning does not necessarily guarantee that Maria trained hard. This is the connection we will need to focus on when considering the answer choices.

To further abstract this relationship, we can portray the argument as follows:

Premise:  Maria won (which we could also call “A”) 
 Conclusion:  Maria trained hard (which we could also call “B”). The answer that will justify this relationship is: A B. Which is the same as: Maria won Maria trained hard. A quick glance at the answer choices reveals that answer choice (C) matches this relationship (remember, “only if” introduces a necessary condition). Thus, the structure in this problem matches the first of the two examples discussed on the previous page. A large number of Justify questions follow this same model, and you should be prepared to encounter this form.

Answer choice (A): This answer does not justify the conclusion that Maria trained hard. The answer does justify the conclusion that Maria trained, but because this is not the same as the conclusion of the argument, this answer is incorrect. Another way of attacking this answer is to use the Justify Formula. Consider the combination of the following two elements: Premise: Maria won this year’s local sailboat race by beating Sue, the winner in each of the four previous years.

Answer choice (A): Sue did not train as hard as Maria trained. Does the combination of the two elements lead to the conclusion that Maria trained hard? No, and therefore the answer is wrong.

Answer choice (B): This is a Mistaken Reversal of what is needed (and therefore the Mistaken Reversal of answer choice (C)). Adding this answer to the premise does not result in the conclusion. In Justify questions featuring conditionality, always be ready to identify and avoid Mistaken Reversals and Mistaken Negations of the relationship needed to justify the conclusion.

Answer choice (C): This is the correct answer. Adding this answer to the premise automatically yields the conclusion.

Answer choice (D): Because we do not know anything about Sue except that she lost, this answer does not help prove the conclusion. If you are having difficulty understanding why this answer is incorrect, use the Justify Formula. Consider the combination of the following two elements: Premise: Maria won this year’s local sailboat race by beating Sue, the winner in each of the four previous years.

Answer choice (C): If Sue trained hard, she would win the sailboat race. The combination of the two creates the contrapositive conclusion that Sue did not train hard. But, the fact that Sue did not train hard does not tell us anything about whether Maria trained hard.

Answer choice (E): Because this answer addresses only the relative speed of the two racers, it fails to help prove that Maria trained hard.

saransh · Answer

C it is .
Use of word "only if" .
If there are more reasons other than hard training when Maria can beat sue then we cannot conclude that training hard is the only reason for Maria's win

Paris75 · Answer

Agree with C.

If X happens than Y will happen;

here it only works in one direction.

therefore, if Y happens, than X did not necessary happen too.

Answer C.

Icecream87 · Answer

not thAn, thEn dear :-D

Otherwise, C as well. This is the conditional clause that validates the conclusion without a doubt.

NikGujju · Answer

Okay ! so the contention of doubt is between B and C. 
Before that, always remember that winning does not necessarily mean that the person has worked hard, may be the competitor gave up or was not prepared.

B: "if" .. This is a mistaken reversal of what is needed. We know this, but does it necessarily mean that she worked hard? If leads us to a probabilistic situation 
C: Adding this choice to premise takes us to the conclusion.

nightblade354 · Answer

For anyone wondering, this is actually an LSAT JUSTIFY question, and NOT an assumption question. The OA is correct, but it is worth pointing out in case there is any confusion moving forward

Lowkya · Answer

Conclusion:   Because Maria trained hard, she could beat Sue, who was champion for 4 years.

Assumption:  If Maria did not train hard, she couldn't beat Sue in the race.

(A) Sue did not train as hard as Maria trained.  - Negating this statement does not break conclusion.

(B) If Maria trained hard, she would win the sailboat race.  - Cannot tell about this based on given premise.

(C) Maria could beat a four-time winner only if she trained hard.  - Yes, clearly the assumption.

(D) If Sue trained hard, she would win the sailboat race.  - Cannot comment on Sue from given Premise.

(E) Sue is usually a faster sailboat racer than Maria.  - We cannot comment who is fast from the given premise.

mallya12 · Answer

Option C is correct. But how do I eliminate option B.

Negation of B
If Maria didn't train hard, she would win the sailboat race.
So this breaks the conclusion that Maria trained hard.

Please clarify my doubt.

GMATNinja · Answer

anairamitch1804  has done a nice job explaining (B) vs (C) in  this  post. Let us know if you have any further questions!

mallya12 · Answer

I didn't understand clearly, say if there was an option choice which stated Maria trained hard, so she will win the race would this be the right answer. how do I use negation technique to eliminate between B and C? Thank You

unraveled · Answer

Maria won this year’s local sailboat race by beating Sue, the winner in each of the four previous years. We can conclude from this that Maria trained hard.

The conclusion follows logically if which one of the following is assumed?

(A) Sue did not train as hard as Maria trained.

(B) If Maria trained hard, she would win the sailboat race.

(C) Maria could beat a four-time winner only if she trained hard.

(D) If Sue trained hard, she would win the sailboat race.

(E) Sue is usually a faster sailboat racer than Maria.

It was B and C that confused me just like anyone. But I found C relatively better than B. C left no scope of error in judgement. In B, I found that even if Maria trained hard, it is possible that during a slight error might have costed her the race or may be Sue got little lucky. So there are many number of possibilities that can exist still.

In C, two things just slashed the requirement - beating a four-time winner and only if.

ndwz · Answer

I actually only rejected C because I thought this was not a necessary assumption question but a sufficient assumption question

How do I avoid this grave error in the future?

GMATNinja · Answer

Often, when test-takers try label or categorize questions, they become blinded to the details in the passage and/or answer choices. So instead of thinking about what "kind" of question it is, focus on the specific details of the language used in the passage and the answer choices.

(Fwiw, we say a bit about this in our  CR Guide for Beginners , and  this CR video  is basically an hourlong workshop on the pitfalls of obsessing over question types.)

In this case, the words "only if" are the key to choice (C). That means that Maria COULD NOT HAVE beaten a four-time winner UNLESS she trained hard. Since she did beat a four-time winner, we know that she did in fact train hard.

Notice that we aren't really worrying about "necessary vs. sufficient" in that analysis. Your "grave error" was that you transformed the question into something like, "which of the following assumptions is sufficient?". This attempt to categorize and simplify the question distracted you from the basic logic of the passage, which is what they are asking about.

I hope that helps!

rahul5657 · Answer

(A) Sue did not train as hard as Maria trained.
This compares effort levels but doesn’t prove that Maria trained hard.
Maybe Maria trained a little and Sue trained not at all.
Doesn’t guarantee the conclusion.
 Incorrect

(B) If Maria trained hard, she would win the sailboat race.
This is backwards: it says hard training leads to winning — but Maria already won.
Doesn’t help prove that she trained hard.
 Incorrect

(C) Maria could beat a four-time winner only if she trained hard.
This says: If Maria didn’t train hard, she couldn’t have beaten Sue.
Since Maria did beat Sue, she must have trained hard.
This makes the conclusion logically follow.
 Correct

(D) If Sue trained hard, she would win the sailboat race.
Even if true, doesn’t prove that Maria trained hard.
Maybe Sue had a bad day or didn’t train — doesn’t guarantee anything about Maria.
 Incorrect

(E) Sue is usually a faster sailboat racer than Maria.
This suggests Maria winning is surprising — but doesn’t prove why (training or something else).
It may support the idea Maria needed to improve, but doesn’t guarantee she trained hard.
 Incorrect

Maria won this year’s local sailboat race by beating Sue, the winner

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GMAT Critical Reasoning (CR) Questions

Maria won this year’s local sailboat race by beating Sue, the winner

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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My Rewards