critical reasoning

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critical reasoning

by shrutib » Wed May 30, 2012 10:18 am
8. No horse finished ahead of Cold Molasses, and no horse finished behind Bag O'Bones. Also, no horse finished between Cold Molasses and Three-Leg Charlie. Therefore (assume no ties):

A) Cold Molasses finished second or third.

B) Bag O'Bones came in fourth or better.

C) Three-Leg Charlie finished either second or third.

D) Three-Leg Charlie may have finished first, but at least he did not finish last.

E) Bag O'Bones finished ahead of Cold Molasses.

My choice was B.The answer says C. I think its wrong.
Source: — Critical Reasoning |

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by Jim@StratusPrep » Wed May 30, 2012 10:37 am
No horse finished ahead of Cold Molasses -- > Cold Molasses is first
no horse finished behind Bag O'Bones --> Bag O'bones is last
no horse finished between Cold Molasses and Three-Leg Charlie --> Three-Leg Charlie is second

B is wrong because you have no idea how many horses are in the race
C is right because he would have had to finish second (not sure how third comes into play)
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by dhonu121 » Wed May 30, 2012 10:39 am
Draw a diagram.
C it is.
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by Kasia@EconomistGMAT » Wed May 30, 2012 10:49 am
c is correct because only one of the two statements connected with "or" must be true to make the whole true.
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by shrutib » Wed May 30, 2012 11:00 am
If no one is there between Cold Molasses and three legged Charlie, then the possibility of his finishing the third does not even arise. But since , we do not know the horse count,Bag O'Bones can be fourth or better. Where am i going wrong?

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by Kasia@EconomistGMAT » Thu May 31, 2012 2:40 am
The question posted was incomplete. It is a part of a longer task:

Questions 4 and 5 refer to the following scenario.

In a horse race involving six horses, three of the entries were Bag O'Bones, Cold Molasses, and Three-Leg Charlie. All six horses finished one after the other.

4. No horse finished ahead of Cold Molasses, and no horse finished behind Bag O'Bones. Also, no horse finished between Cold Molasses and Three-Leg Charlie. Therefore,

A) Cold Molasses finished second or third.

B) Bag O'Bones came in fourth or better.

C) Three-Leg Charlie finished second or third.

D Three-Leg Charlie may have finished first, but at least he did not finish last.

E) Bag O'Bones finished ahead of Cold Molasses.

Once we know there were 6 horses, we have enough data to know the position of each of the horses

And you can try to crack number 5:

5. Four horses finished between Bag O'Bones and Cold Molasses. Therefore,

A) Cold Molasses finished last.

B) Bag O'Bones finished second or third.

C) Bag O'Bones finished fifth.

D) Three-Leg Charlie did not finish last.

E) either Bag O'Bones finished fifth, or Three-Leg Charlie came in third.
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by Ashujain » Thu May 31, 2012 2:42 am
shrutib wrote:If no one is there between Cold Molasses and three legged Charlie, then the possibility of his finishing the third does not even arise. But since , we do not know the horse count,Bag O'Bones can be fourth or better. Where am i going wrong?
To understand it better please have a look at below:
X or Y is true if either X is true or Y is true or both are true
X and Y is true only if X and Y both are true. If either of them is false then the whole statement is false.

Now consider B: Bag O'Bones came in fourth or better.
Here X is Bag O'Bones came in fourth and Y is Bag O'Bones came better than fourth.
Can u tell for sure which is true: X/Y? NO
From the information provided in the argument we do not know anything about the no. of horses so we can not exactly say anything about the position of Bag O'Bones.

Now consider C: Three-Leg Charlie finished either second or third.
Here X is Three-Leg Charlie finished second and Y is Three-Leg Charlie finished third
Can u tell for sure which is true: X/Y? Yes
Because it is clear from the argument that Three-Leg Charlie finished second. Although, Y is false, but X is true; so it makes the complete statement true.

Hope it helps!

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by ramprakaashk » Mon Jun 04, 2012 7:37 pm
Hi ,

For the 5th question ,

the answer is D : Charlie did not finish last.