BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem
TTP OnDemand GMAT Video Course
Featured Course

Target Test Prep GMAT OnDemand

Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.

  • 715+ score guarantee — highest in the industry (99th percentile)
  • 52 chapters · 1,500+ lessons · 4,000+ practice questions
  • 400 hours of video · 1,500+ instructor-led HD smartboard lessons
  • 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
  • 24/7 live support + weekly Zoom office hours with GMAT instructors
  • TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
  • 1,200+ flashcards + AI-powered study assistant & daily calendar
  • OnDemand, LiveTeach & GMAT Bootcamp formats available
  • Also: GRE, SAT Math & Executive Assessment courses
  • MBA Admissions Consulting now available
  • 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
  • 200,000+ students served
  • 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★ 5.0 (559 reviews)
130-pt guarantee
$0 to start then $127/mo
Start Free 5-Day Trial Read 559 Reviews →

DS - Div/Primes: If the integer n is greater than 1, is n =

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
Master | Next Rank: 500 Posts
Posts: 400
Joined: Mon Dec 10, 2007 1:35 pm
Location: London, UK
Thanked: 19 times
GMAT Score:680
by II » Sun Aug 10, 2008 9:12 am
If the integer n is greater than 1, is n equal to 2?

(1) n has exactly two positive factors

(2) The difference of any two distinct positive factors of n is odd

I know the answer to this ... but wanted to understand more on statement 2.

Thanks.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |
Legendary Member
Posts: 683
Joined: Tue Jul 22, 2008 1:58 pmFollowed by: 2 members
Location: Dubai
Thanked: 73 times

by mals24 » Sun Aug 10, 2008 11:25 am
IMO B

st 1 says n is prime it could be any prime number INSUFF

st 2 says The difference of any two distinct positive factors of n is odd
This st means that if we subtract any two positive factors of n the difference should be odd.
the only number that satisfies this condition is 2
for example take foll numbers:
factors of 3 = 1,3 3-1=odd
factors of 4= 4,1,2 4-1=odd but 4-2even
factors of 10 = 10, 1, 5, 2 10-1=odd; 5-1=even
so on and so forth

i hope the explanation was clear for st 2
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
User avatar
Master | Next Rank: 500 Posts
Posts: 400
Joined: Mon Dec 10, 2007 1:35 pm
Location: London, UK
Thanked: 19 times
GMAT Score:680

by II » Sun Aug 10, 2008 1:32 pm
sure I got this !
... I think you meant to say "3-1 = even" !
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 683
Joined: Tue Jul 22, 2008 1:58 pmFollowed by: 2 members
Location: Dubai
Thanked: 73 times

by mals24 » Mon Aug 11, 2008 5:43 am
woops sorry for the typo
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Master | Next Rank: 500 Posts
Posts: 203
Joined: Wed Jun 04, 2008 1:01 am
Location: Windsor
Thanked: 5 times
GMAT Score:650

by jsl » Mon Aug 11, 2008 6:16 am
mals24 wrote:IMO B

st 2 says The difference of any two distinct positive factors of n is odd
This st means that if we subtract any two positive factors of n the difference should be odd.
Is the official answer definitely B? If you pick 6, factors include 1, 2, 3, 6. If you subtract 2 from 3, the remainder is odd...

I thought the answer is C...
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 683
Joined: Tue Jul 22, 2008 1:58 pmFollowed by: 2 members
Location: Dubai
Thanked: 73 times

by mals24 » Mon Aug 11, 2008 6:38 am
@jsl
But if you subtract 2 from 6, the answer is even so that eliminates 6 as an option and narrows down the option to 2 hence B is SUFF..

The factors of an odd # are always odd and every time u subtract 2 odd # the answer is even so that eliminates all odd #s

The factors of all even # (except 2) are a combination of more than 2 even n odd # so there will be at least one pair of factors which when you subtract the answer will be even. so that eliminates all even # except 2

I hope its clear
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Newbie | Next Rank: 10 Posts
Posts: 1
Joined: Sun Feb 15, 2009 3:09 pm

by lanm03 » Sun Feb 15, 2009 3:16 pm
I think the confusing part of the question is the word "any":

"The difference of any two distinct positive factors of n is odd."

Factors of 10: 1, 2, 5, 10
5-2=3 (odd)

Factors of 6: 1, 2, 3, 6
3-2=1 (odd)

With this reasoning, n could be 10 or 20.

I think by changing the word "any" to "every" makes more sense. Just a thought...

BTW, the answer according to the book is B. I'm just pointing out an observation.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1