1000 CR's Test A....

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1000 CR's Test A....

by smclean23 » Wed Jul 09, 2008 6:27 pm
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.
Source: — Critical Reasoning |

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by reachac » Wed Jul 09, 2008 8:35 pm
IMO C

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by raunekk » Wed Jul 09, 2008 9:47 pm
imo:C

It is know as contrapositive.

It comes under conditional reasoning



Read CR bible to understand this properly.

thanks

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by newera » Sat Jul 12, 2008 6:16 pm
Definitely C.

and raunekk is absolutely right, CR did an awesome job at explaining this.

From that list of relationships you gave,
A-->B
B-->C
C-->D
So we can also say A-->D. The contrapositive is switching it around and adding "not". so not D-->not A

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by peter.p.81 » Wed May 11, 2016 12:42 am
I'd say C but I'm afraid more because of my intuition than any logic.