It is currently 19 Feb 2018, 07:51

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.

Close

Request Expert Reply

Confirm Cancel

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

N and M are each 3-digit integers...

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Intern
Intern
avatar
B
Joined: 22 Dec 2016
Posts: 6
N and M are each 3-digit integers... [#permalink]

Show Tags

New post 06 Apr 2017, 18:17
1
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

38% (03:43) correct 63% (01:39) wrong based on 8 sessions

HideShow timer Statistics

N and M are each 3-digit integers. Each of the numbers 1, 2, 3, 6, 7, and 8 is a digit for either N or M. What is the smallest possible positive difference between N and M?

A: 29

B: 49

C: 58

D: 113

E: 131
[Reveal] Spoiler: OA
Manager
Manager
avatar
S
Joined: 17 Apr 2016
Posts: 102
Re: N and M are each 3-digit integers... [#permalink]

Show Tags

New post 06 Apr 2017, 18:26
Is trial and error only the way to solve this problem? With trail and error technique it might take time, so is there a specific technique to solve such type of question?
Intern
Intern
avatar
B
Joined: 22 Dec 2016
Posts: 6
Re: N and M are each 3-digit integers... [#permalink]

Show Tags

New post 06 Apr 2017, 18:47
adityapareshshah wrote:
Is trial and error only the way to solve this problem? With trail and error technique it might take time, so is there a specific technique to solve such type of question?
I'm trying to figure out the same thing, if people are able to offer up a suggestion. I got this question wrong. I started with the units digit and worked to hundreds, but the lowest value I was able to get in 2 minutes was 49.


Sent from my iPhone using GMAT Club Forum mobile app
1 KUDOS received
Intern
Intern
avatar
B
Joined: 29 Apr 2015
Posts: 23
GPA: 3.89
N and M are each 3-digit integers... [#permalink]

Show Tags

New post 06 Apr 2017, 19:31
1
This post received
KUDOS
adamodom1 wrote:
N and M are each 3-digit integers. Each of the numbers 1, 2, 3, 6, 7, and 8 is a digit for either N or M. What is the smallest possible positive difference between N and M?

A: 29

B: 49

C: 58

D: 113

E: 131


I got the right answer in 2:30 using a strategic guess and check

After my first guess I quickly realized that the hundreds place would make the biggest difference and I'd have to use the rest to make the smaller number as large as possible and the larger small. I arbitrarily chose 1,2 for hundreds and got:

187
236

Then I realized that by using 6,7 for hundreds instead of 1,2 I could be more effective and narrowing the gap so I got:

683
712

I checked the delta and noticed that it was the smaller answer offered so I knew I was done.
Director
Director
avatar
G
Joined: 07 Dec 2014
Posts: 906
Re: N and M are each 3-digit integers... [#permalink]

Show Tags

New post 06 Apr 2017, 21:17
adamodom1 wrote:
N and M are each 3-digit integers. Each of the numbers 1, 2, 3, 6, 7, and 8 is a digit for either N or M. What is the smallest possible positive difference between N and M?

A: 29

B: 49

C: 58

D: 113

E: 131


this seems to work for any 6-digit sequence like this:
use the 2nd digit above the median as the 100s place for the higher 3-digit number
and use the 1st and 2nd digits for the 10s and 1s places respectively: 712
use the 1st digit above the median as the 100s place for the lower 3-digit number
and use the 6th and 3rd digits for the 10s and 1s places respectively: 683
712-683=29
A
Intern
Intern
avatar
S
Joined: 05 Sep 2016
Posts: 21
Location: Israel
Concentration: Economics, Technology
WE: Engineering (Telecommunications)
Re: N and M are each 3-digit integers... [#permalink]

Show Tags

New post 06 Apr 2017, 21:56
Answer A.
N = 712. M = 683. N-M=29. This is the smallest option. No need to check other combinations.

Sent from my Redmi 4 using GMAT Club Forum mobile app
Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 43804
Re: N and M are each 3-digit integers... [#permalink]

Show Tags

New post 06 Apr 2017, 21:58
adamodom1 wrote:
N and M are each 3-digit integers. Each of the numbers 1, 2, 3, 6, 7, and 8 is a digit for either N or M. What is the smallest possible positive difference between N and M?

A: 29

B: 49

C: 58

D: 113

E: 131


This question is discussed here: https://gmatclub.com/forum/n-and-m-are- ... 35452.html
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 43804
Re: N and M are each 3-digit integers... [#permalink]

Show Tags

New post 07 Apr 2017, 06:47
adamodom1 wrote:
N and M are each 3-digit integers. Each of the numbers 1, 2, 3, 6, 7, and 8 is a digit for either N or M. What is the smallest possible positive difference between N and M?

A: 29

B: 49

C: 58

D: 113

E: 131


Please follow the rules when posting a question. Thank you.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Re: N and M are each 3-digit integers...   [#permalink] 07 Apr 2017, 06:47
Display posts from previous: Sort by

N and M are each 3-digit integers...

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


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

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®.