1000 CR - Query

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1000 CR - Query

by Sharad.Inc » Tue Apr 17, 2007 3:18 am
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.

Why is the answer C and not B ?

Thanks in advance !

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by bww » Sun May 13, 2007 8:11 pm
something with contrapositives?

"If A, then B" corresponds to "If not B, then not A." It is not "If not A, then not B." ??

Thus, "if not D, then not A" adheres. "If not B, then not C" does not follow the same logic (it would be "if not C, the not B").

???

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by BTGmoderatorRO » Fri Sep 22, 2017 7:47 pm
If A, then B. which can also be interpreted as (if not B, then not A).
Both B and C are wrong.
I think this follows the Alphabet sequence. Hence, option D will be considered by me as the right option.