It is currently 18 Nov 2017, 15:00

### 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

# From OG, How many different positive intergers are factors

 post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
Manager
Joined: 04 Jun 2003
Posts: 61

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

From OG, How many different positive intergers are factors [#permalink]

### Show Tags

31 Jan 2004, 18:48
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

From OG,
How many different positive intergers are factors of 441?

This question is, per se, easy. But, who can demonstrate the most elegant approach, other than traditional method, to solve it?

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

Director
Joined: 28 Oct 2003
Posts: 501

Kudos [?]: 34 [0], given: 0

Location: 55405

### Show Tags

02 Feb 2004, 08:27
Wouldn't the most elegant approach be a simple factorization?
441=
3*3*7*7

1, 3, 9, 21, 63, 147, 441

Kudos [?]: 34 [0], given: 0

SVP
Joined: 30 Oct 2003
Posts: 1788

Kudos [?]: 114 [0], given: 0

Location: NewJersey USA

### Show Tags

02 Feb 2004, 09:46
Hi stoolfi,

You mean factorization into primes.

3^2 * 7^2

3^1, 3^2, 3*7^1, 3*7^2, 3^2*7^1, 3^2*7^2
7, 7^2

7 factors.

Kudos [?]: 114 [0], given: 0

Senior Manager
Joined: 11 Nov 2003
Posts: 356

Kudos [?]: 5 [0], given: 0

Location: Illinois

### Show Tags

02 Feb 2004, 10:45
stoolfi wrote:
Wouldn't the most elegant approach be a simple factorization?
441=
3*3*7*7

1, 3, 9, 21, 63, 147, 441

Stoolfi,

Why you omitted 7 and 49? Total should 9 factors

Kudos [?]: 5 [0], given: 0

SVP
Joined: 30 Oct 2003
Posts: 1788

Kudos [?]: 114 [0], given: 0

Location: NewJersey USA

### Show Tags

02 Feb 2004, 11:41
yeah there should be 9 factors. I did not include 1

Kudos [?]: 114 [0], given: 0

Director
Joined: 28 Oct 2003
Posts: 501

Kudos [?]: 34 [0], given: 0

Location: 55405

### Show Tags

02 Feb 2004, 11:56
Quote:
Why you omitted 7 and 49? Total should 9 factors.

Human error. D'oh!

Kudos [?]: 34 [0], given: 0

Manager
Joined: 04 Jun 2003
Posts: 61

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

### Show Tags

02 Feb 2004, 19:01
Thanx a lot,
I just learn from other comparable topic in this GMAT webboard that this genre of question we can apply:
441 = (3^2)*(7^2)

thus, we have 9 factors; that are {1,3,9}*{1,7,49) = 9 patterns

Well, try another OG quiz,

If n=4p where p is a prime number greater than 2, how many different positive even divisors does n have, including n?

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

02 Feb 2004, 19:01
Display posts from previous: Sort by

# From OG, How many different positive intergers are factors

 post reply Question banks Downloads My Bookmarks Reviews Important topics

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®.