It is currently 22 Nov 2017, 19:10

### 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

# Can teh positive integer n be written as the sum of two

Author Message
Manager
Joined: 23 Mar 2008
Posts: 216

Kudos [?]: 203 [0], given: 0

Can teh positive integer n be written as the sum of two [#permalink]

### Show Tags

31 Mar 2008, 11:08
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

Can teh positive integer n be written as the sum of two different positive prime numbers?

1) n is greater than 3
2) n is odd

many thanks

Kudos [?]: 203 [0], given: 0

Intern
Joined: 31 Mar 2008
Posts: 14

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

### Show Tags

31 Mar 2008, 11:14
primes: 1,3,5,7,11,13,17,etc

sum of any two primes is even.

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

Senior Manager
Joined: 20 Dec 2004
Posts: 251

Kudos [?]: 112 [0], given: 0

### Show Tags

02 Apr 2008, 08:33
onyxls1 wrote:

sum of any two primes is even.

5 = 2 + 3 (2 & 3 are prime but 5 is not even)
7 = 2 + 5 (2 & 5 are prime but 7 is not even)
9 = 2 + 7 (2 & 7 are prime but 9 is not even)
13 = 2 + 11 (2 & 11 are prime but 13 is not even)
_________________

Stay Hungry, Stay Foolish

Kudos [?]: 112 [0], given: 0

Current Student
Joined: 28 Dec 2004
Posts: 3345

Kudos [?]: 322 [0], given: 2

Location: New York City
Schools: Wharton'11 HBS'12

### Show Tags

02 Apr 2008, 08:37
I will go with E..

pick 23..23 cannot be expressed as the sum of 2 different primes

13 can be expressed as 11+2

Kudos [?]: 322 [0], given: 2

CEO
Joined: 17 Nov 2007
Posts: 3583

Kudos [?]: 4672 [0], given: 360

Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40

### Show Tags

02 Apr 2008, 08:45
E

1. Let n satisfies both conditions
2. n can be odd only if one of the prime numbers is 2.
3. Therefore, n=p+2
4. p can be prime number (5,7,11,13,17) and can be not prime number (9,15)
5. Therefore, E

we now can also construct two examples:
5=3+2 and 11=9+2
_________________

HOT! GMAT TOOLKIT 2 (iOS) / GMAT TOOLKIT (Android) - The OFFICIAL GMAT CLUB PREP APP, a must-have app especially if you aim at 700+ | PrepGame

Kudos [?]: 4672 [0], given: 360

CEO
Joined: 29 Mar 2007
Posts: 2553

Kudos [?]: 528 [0], given: 0

### Show Tags

02 Apr 2008, 08:54
puma wrote:
Can teh positive integer n be written as the sum of two different positive prime numbers?

1) n is greater than 3
2) n is odd

many thanks

E.

Personally I don't like the wording of this DS question. It can be confusing.

The question is asking can it be the sum of two positve prime numbers. Well really we can answer Yes it can be. It should read "IS n the sum of two different positive prime numbers." Just my opionion there.

Anyway when you get these, follow the same rules that apply to all yes and no questions.

Kudos [?]: 528 [0], given: 0

Re: positive integer   [#permalink] 02 Apr 2008, 08:54
Display posts from previous: Sort by

# Can teh positive integer n be written as the sum of two

Moderator: chetan2u

 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®.