If A, then B.
If B, then C.
If C, then D.
If all of the statements above are true, which of the following must also be true?
(A) If D, then A.
(B) If not B, then not C.
(C) If not D, then not A.
(D) If D, then E.
(E) If not A, then not D.
Given answer is C,but I don't understand how it is C. I would rather go with E.
Can someone please explain me how the given answer is true
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I dont think GMAT ever asks such questions. it does not clearly say what the circumstances are. So such questions should be avoided.
From your question, we can infer that If A then D.
But it only means that if A happens, then D can happen.
It does not in any place suggest that A is the only way of making D happen.
(If you win, I will give you a treat. This does not mean that if you dont win, there is no chance of me giving you treat. I can give you another treat, say, if i score 760 on the GMAT.)
So E is wrong.
But now with C. It says if not D then not A.
Which means D did not happen. We know that D happens if C, C if B and B is A. So if not D, then A dint happen.
From your question, we can infer that If A then D.
But it only means that if A happens, then D can happen.
It does not in any place suggest that A is the only way of making D happen.
(If you win, I will give you a treat. This does not mean that if you dont win, there is no chance of me giving you treat. I can give you another treat, say, if i score 760 on the GMAT.)
So E is wrong.
But now with C. It says if not D then not A.
Which means D did not happen. We know that D happens if C, C if B and B is A. So if not D, then A dint happen.
Vineesh,
Just telling you what I know and think. I am not the expert.
Just telling you what I know and think. I am not the expert.
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IMO questions wth heavy formal logic are not expected on GMAT(an advice frm an expert too few days back in this forum).
but i still tried this Q
A)- Q only says if C occurs D occurs but C is not the only way, there may well be others too
B)-if not B then not A is correct, cant say abt C
C) - if not D->not C->notB->notA
D)no mention of E
E)same logic as A
HTH
Cheers,
but i still tried this Q
A)- Q only says if C occurs D occurs but C is not the only way, there may well be others too
B)-if not B then not A is correct, cant say abt C
C) - if not D->not C->notB->notA
D)no mention of E
E)same logic as A
HTH
Cheers,
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Hi,
This is based on a simple concept: the concept is
So if X -> Y then the following conclusions are wrong:
Y -> X
X (NOT) -> Y (NOT)
Only the following conclusion is right:
Y (not) -> X (not)
In your question,
we get, A -> B -> C -> D => A -> D
Hence from u can state that D(NOT) -> A(NOT)
This is based on a simple concept: the concept is
So if X -> Y then the following conclusions are wrong:
Y -> X
X (NOT) -> Y (NOT)
Only the following conclusion is right:
Y (not) -> X (not)
In your question,
we get, A -> B -> C -> D => A -> D
Hence from u can state that D(NOT) -> A(NOT)