It is currently 24 Mar 2018, 04:32

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# If A, then B. If B, then C. If C, then D. If all of the

Author Message
Manager
Joined: 21 Jul 2006
Posts: 58
If A, then B. If B, then C. If C, then D. If all of the [#permalink]

### Show Tags

15 Feb 2009, 21:07
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions

### HideShow timer Statistics

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.

--== Message from GMAT Club Team ==--

This is not a quality discussion. It has been retired.

If you would like to discuss this question please re-post it in the respective forum. Thank you!

To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative | Verbal Please note - we may remove posts that do not follow our posting guidelines. Thank you.
Director
Joined: 12 Oct 2008
Posts: 506

### Show Tags

15 Feb 2009, 21:29
IMO B
Senior Manager
Joined: 14 Mar 2007
Posts: 277
Location: Hungary

### Show Tags

16 Feb 2009, 04:13
Manager
Joined: 21 Jul 2006
Posts: 58

### Show Tags

16 Feb 2009, 08:51
Hi:

The OA is C. Could someone explain why it is "C" and not any other response.

Thanks,

Chalven
Senior Manager
Joined: 26 May 2008
Posts: 420
Schools: Kellogg Class of 2012

### Show Tags

16 Feb 2009, 09:00
chalven wrote:
Hi:

The OA is C. Could someone explain why it is "C" and not any other response.

Thanks,

Chalven

D is the contra positive of the original statement. If I cut the explanation short,

If A -> D, then the correct answer choice can be either A-->D or NotD-->NotA. Every other inference is incorrect

Cheers,
Unplugged
Manager
Joined: 21 Jul 2006
Posts: 58

### Show Tags

16 Feb 2009, 11:08
D is the contra positive of the original statement. If I cut the explanation short,

If A -> D, then the correct answer choice can be either A-->D or NotD-->NotA. Every other inference is incorrect

Cheers,
Unplugged

Then, How about answer choice "E?" Why is it wrong? Could you be a little more detail.

Thank you, Chalven.
Senior Manager
Joined: 14 Mar 2007
Posts: 277
Location: Hungary

### Show Tags

16 Feb 2009, 13:00
Great help for logic:

viewtopic.php?t=14547
Senior Manager
Joined: 14 Mar 2007
Posts: 277
Location: Hungary

### Show Tags

17 Feb 2009, 01:56
The statements above says that if A then D. But if not A then D can still happen. For example, C=Not A -> D happens.
Senior Manager
Joined: 26 May 2008
Posts: 420
Schools: Kellogg Class of 2012

### Show Tags

17 Feb 2009, 09:06
chalven wrote:
D is the contra positive of the original statement. If I cut the explanation short,

If A -> D, then the correct answer choice can be either A-->D or NotD-->NotA. Every other inference is incorrect

Cheers,
Unplugged

Then, How about answer choice "E?" Why is it wrong? Could you be a little more detail.

Thank you, Chalven.

E is mistaken negation. Hence wrong

Cheers,
Unplugged
Intern
Joined: 30 Jul 2009
Posts: 39

### Show Tags

31 Jul 2009, 11:14
For this question , I came up with substitution.

if it moves itself with 4 wheels then it is car
if car then it is vehicle

A -> anything that moves itsef with 4 wheels
B -> Car
C-> engine

Option A: If man-made (D) then it moves itself with 4 wheels (A) - False. There are many many man-made items that doesn't move with 4 wheels ex. Table
option B: if not a car then not an engine - False. If it is not car it can be anything else ex. chair
option C: if engine(C) then it is man-made (D)- true
option D: If man-made (d) then E - False - No E in the question
option E: If it doesn't move by itself(A) then not man-made (D) - False.There are many many man-made items that doesn't move with 4 wheels ex. Table

So clearly C is the best ans

--== Message from GMAT Club Team ==--

This is not a quality discussion. It has been retired.

If you would like to discuss this question please re-post it in the respective forum. Thank you!

To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative | Verbal Please note - we may remove posts that do not follow our posting guidelines. Thank you.
Re: CR Question.   [#permalink] 31 Jul 2009, 11:14
Display posts from previous: Sort by

# If A, then B. If B, then C. If C, then D. If all of the

Moderators: GMATNinjaTwo, GMATNinja

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.