Find all School-related info fast with the new School-Specific MBA Forum

It is currently 29 Jul 2015, 06:30
GMAT Club Tests

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

PR and MN are 2-digit positive integers, where P, R, M, and

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Current Student
User avatar
Joined: 11 May 2008
Posts: 560
Followers: 7

Kudos [?]: 64 [0], given: 0

PR and MN are 2-digit positive integers, where P, R, M, and [#permalink] New post 01 Aug 2008, 02:14
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

PR and MN are 2-digit positive integers, where P, R, M, and N are digits of the two numbers, and are different from each other. If the tens' digit of sum of PR and MN is M, which of the following must be true?
I. M<9
II. R+N>9
III. P>8
A. I only
B. II only
C. III only
D. I and II
E. I, II and III
Current Student
User avatar
Joined: 11 May 2008
Posts: 560
Followers: 7

Kudos [?]: 64 [0], given: 0

Re: incomplete positive integers [#permalink] New post 01 Aug 2008, 03:48
expln pls nikhil... so tat others can learn...
Senior Manager
Senior Manager
avatar
Joined: 16 Jul 2008
Posts: 289
Schools: INSEAD Dec'10
Followers: 2

Kudos [?]: 15 [0], given: 4

Re: incomplete positive integers [#permalink] New post 01 Aug 2008, 04:03
I'm going for E.

This forum is fun ;)

EDIT: so, we know that "something plus M equals 10 + M". From there we get:

R + N > 9
1 + P + M = 10 + M --> P = 9 --> P > 8

But P, R, M and N are different, therefore M cannot be 9. So: M < 9.
_________________

http://applicant.wordpress.com/

VP
VP
avatar
Joined: 17 Jun 2008
Posts: 1404
Followers: 8

Kudos [?]: 165 [0], given: 0

Re: incomplete positive integers [#permalink] New post 03 Aug 2008, 00:10
arjtryarjtry wrote:
PR and MN are 2-digit positive integers, where P, R, M, and N are digits of the two numbers, and are different from each other. If the tens' digit of sum of PR and MN is M, which of the following must be true?
I. M<9
II. R+N>9
III. P>8
A. I only
B. II only
C. III only
D. I and II
E. I, II and III


say x=10p+r and y=10m+n => x+y= 10(p+m)+r+n

p+m=m when r+n > 9 hence II is must
now carry from r+n is 1 hence p+m+1 =10a+m a is any number
is possible when p=9 and m <9 => III and I are must

hence I,II and III are must
IMO E
_________________

cheers
Its Now Or Never

Intern
Intern
avatar
Joined: 02 Aug 2008
Posts: 29
Followers: 0

Kudos [?]: 2 [0], given: 0

Re: incomplete positive integers [#permalink] New post 03 Aug 2008, 01:10
a number like 41 and 32 proves that (2) need not be right. Apart from m <9, i don't find anything "must"
did i do anything wrong?
Senior Manager
Senior Manager
avatar
Joined: 16 Jul 2008
Posts: 289
Schools: INSEAD Dec'10
Followers: 2

Kudos [?]: 15 [0], given: 4

Re: incomplete positive integers [#permalink] New post 03 Aug 2008, 03:22
nishchals wrote:
a number like 41 and 32 proves that (2) need not be right. Apart from m <9, i don't find anything "must"
did i do anything wrong?


41 + 32 = 73. The tens digit is 7, I think you are looking at the units digit.
_________________

http://applicant.wordpress.com/

Manager
Manager
avatar
Joined: 23 Apr 2008
Posts: 90
Followers: 1

Kudos [?]: 6 [0], given: 0

Re: incomplete positive integers [#permalink] New post 03 Aug 2008, 06:00
IMO E

PR
+ MN
_____

CLEARLY IF P IS NOT EQUAL TO M,THEN P+M CANT BE EQUAL TO M
UNLESS R+N>9

NOW THE CARRY CARRY FWD DIGIT WILL BE 1 ONLY (CANT B GREATER THAN 1)

SO P+1+M IS EQUAL TO M(ACC TO QUES)
WHICH IS NOT POSSIBLE IF P<8

NOW COS P CANT B LESS THAN 8,IT HAS TO BE 9
THEREFORE M HAS TO BE LES THAN 9

HENCE ALL TRUE
Re: incomplete positive integers   [#permalink] 03 Aug 2008, 06:00
Display posts from previous: Sort by

PR and MN are 2-digit positive integers, where P, R, M, and

  Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Privacy Policy| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

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®.