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I have been trying CR questions based on logic i.e. A [#permalink]
08 Feb 2008, 10:41
Question Stats:
0% (00:00) correct
0% (00:00) wrong based on 0 sessions
I have been trying CR questions based on logic i.e. A implies B, not B implies not A, etc. This has been my weakest link so far…having done 70 questions, more than half of my answers are wrong. I am feeling really demoralized…:(
Can some kind soul explain, for example, how to break down and solve the following two questions?
Question 1
Most parents who are generous are good parents, but some self-centered parents are also good parents. Yet all good parents share one characteristic: they are good listeners.
If all the statements in the passage are true, which one of the following must also be true?
(A) All parents who are good listeners are good parents. (B) Some parents who are good listeners are not good parents. (C) Most parents who are good listeners are generous. (D) Some parents who are good listeners are self-centered. (E) Fewer self-centered parents than generous parents are good listeners.
Question 2
No senator spoke at the convention unless he or she was a Democrat. No Democrat both spoke at the convention and was a senator.
Which one of the following conclusions can be correctly drawn from the statements above?
(A) No one but senators spoke at the convention (B) No Democrat spoke at the convention. (C) Only Democrats spoke at the convention. (D) No senator spoke at the convention. (E) Some Democrat senators spoke at the convention.
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Re: CR - A implies B, not B implies not A, etc [#permalink]
08 Feb 2008, 10:49
1E 2D
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Re: CR - A implies B, not B implies not A, etc [#permalink]
08 Feb 2008, 11:57
Question 1
Some generous parents---->Good parent Some self-cen parents----->Good parent
All Good parent----->Good listener
When you combine you get
Some generous parents---->Good parent---->Good Listener Some self-cen parents----->Good parent---->Good Listener
(D) Some parents who are good listeners are self-centered
Some of the self-centered parents are good parents and if you a good parent then you are a good listener. So atlest some of the self-centered parents are good listeners.
On the GMAT there is no difference between 'most' and 'some'. They are both particular statements.
Question 2
If both Senator and spoke----->Democrat If spoke and Senator---------> Not Democrat
If a Senator spoke then they would have to be a Democrat, but no Democratic Senator spoke. So the only thing know for sure is that a Senator didnt speak.
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Re: CR - A implies B, not B implies not A, etc [#permalink]
08 Feb 2008, 12:12
Your answers are correct. Brilliant!  However I have a query... You said that on the GMAT there is no difference between 'most' and 'some'. They are both particular statements. If that is the case, then shouldn't (C) be an answer as well? (C) is "Most parents who are good listeners are generous.", which accordingly would be equivalent to "Some parents who are good listeners are generous. So there would be two answers to this question, no? Or is the meaning of "most" in the given passage supposed to be different from the meaning of "most" in answer (C)?
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Re: CR - A implies B, not B implies not A, etc [#permalink]
08 Feb 2008, 12:42
Tom Badgerlock wrote: Your answers are correct. Brilliant!  However I have a query... You said that on the GMAT there is no difference between 'most' and 'some'. They are both particular statements. If that is the case, then shouldn't (C) be an answer as well? (C) is "Most parents who are good listeners are generous.", which accordingly would be equivalent to "Some parents who are good listeners are generous. So there would be two answers to this question, no? Or is the meaning of "most" in the given passage supposed to be different from the meaning of "most" in answer (C)? The problem with "Most parents who are food listeners are generous is that you dont know how much of the second group ( good parents) are made up of generous parents. For these questions just think what is easier to prove. ex. Most people who are on gmatclub will score high or Some people who are on gmatclub will score high. I agree that some good listeners are self-centered and some are generous. But Most is harder to prove that some so I went with D.
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Re: CR - A implies B, not B implies not A, etc
[#permalink]
08 Feb 2008, 12:42
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