Last visit was: 23 Apr 2026, 10:26 It is currently 23 Apr 2026, 10:26
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
User avatar
I3igDmsu
Joined: 25 May 2009
Last visit: 26 Jan 2015
Posts: 104
Own Kudos:
690
 [24]
Given Kudos: 2
Concentration: Finance
GMAT Date: 12-16-2011
12
Kudos
Add Kudos
12
Bookmarks
Bookmark this Post
User avatar
timetrader
Joined: 16 Mar 2009
Last visit: 18 Sep 2015
Posts: 97
Own Kudos:
Given Kudos: 19
Location: Bologna, Italy
Posts: 97
Kudos: 1,434
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
I3igDmsu
Joined: 25 May 2009
Last visit: 26 Jan 2015
Posts: 104
Own Kudos:
Given Kudos: 2
Concentration: Finance
GMAT Date: 12-16-2011
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
IanStewart
User avatar
GMAT Tutor
Joined: 24 Jun 2008
Last visit: 17 Apr 2026
Posts: 4,143
Own Kudos:
Given Kudos: 99
Expert
Expert reply
Posts: 4,143
Kudos: 11,271
Kudos
Add Kudos
Bookmarks
Bookmark this Post
I3igDmsu

2: If x is even, True (excludes x = 0)

There's no reason to exclude 0. Zero is definitely divisible by 2;

I3igDmsu

4: If the ones and tens digits of x are divisible by 4, True

You mean: if the tens and ones digits form a number which is divisible by 4. The number 31,212 is divisible by 4, for example, because the last two digits form a number (12) which is divisible by 4, even though the tens digit and the ones digit are not individually divisible by 4.

I3igDmsu

5: If the ones digit is a 0 or 5, True (excludes x = 0)

There's no reason to exclude 0. Zero is definitely divisible by 5;

I3igDmsu

8: If last 3 digits are divisible by 8, True OR If x is divisible by 2 three times, True

Again for clarity - the last three digits should form a number divisible by 8. For example, 85,328 is divisible by 8 because 328 is divisible by 8 (328 = 8*41).

I3igDmsu

9: If the sum of the digits are 9, True

You mean: If the sum of the digits is a multiple of 9. The sum does not need to equal 9. The number 95,301 is divisible by 9, for example, because the digits add to 18, which is a multiple of 9.

I3igDmsu

10: If the ones digit is 0, True (excludes x=0)

There's no reason to exclude 0. Zero is definitely divisible by 10;
User avatar
I3igDmsu
Joined: 25 May 2009
Last visit: 26 Jan 2015
Posts: 104
Own Kudos:
Given Kudos: 2
Concentration: Finance
GMAT Date: 12-16-2011
Kudos
Add Kudos
Bookmarks
Bookmark this Post
IanStewart - great comments. I've updated everything above.
User avatar
bb
User avatar
Founder
Joined: 04 Dec 2002
Last visit: 23 Apr 2026
Posts: 43,154
Own Kudos:
Given Kudos: 24,677
Location: United States
GMAT 1: 750 Q49 V42
GPA: 3
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
GMAT 1: 750 Q49 V42
Posts: 43,154
Kudos: 83,716
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Thanks! Kudos

Added to the Math Tips Thread: new-to-the-math-forum-please-read-this-first-77764.html
avatar
eddiebeherano
Joined: 02 Feb 2010
Last visit: 23 Feb 2010
Posts: 2
Posts: 2
Kudos: 0
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Quote:


11 Example: Is 824,472 divisible by 11?
Starting with the units digit, add every other number:2 + 4 + 2 = 8. Then add the remaining numbers: 7 + 4 + 8 = 19. Since the difference between these two sums is 11, which is divisible by 11, 824472 is divisible by 11.

If anyone knows any other divisible number properties, please list them. Thanks.

Ok there's maybe one little simplification for the divisibility of number 11:

There's one scheme applied to the digits : - + - + etc. if the forming number is divisible by 11 then our number is divisible by 11.

Lets take for ex 3916 which is divisible by 11.
Application : -3 + 9 - 1 + 6 = 11 -----> so 3916 is divisible by 11.

Another example. 1099989

-1+0-9+9-9+8-9 = -11 --------. so 1099989 is divisible by 11.

Hope it helps.

Eddie
User avatar
anhnguyen990
Joined: 03 Jun 2010
Last visit: 18 Feb 2011
Posts: 29
Own Kudos:
Posts: 29
Kudos: 8
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Thanks ! It helps a lot
User avatar
BeeSkool
Joined: 14 Jun 2010
Last visit: 16 Jan 2012
Posts: 52
Own Kudos:
Given Kudos: 10
Posts: 52
Kudos: 1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
7: Double the ones digit and subtract the last number from the remaining digits. If difference divisible by 7, True


I cannot for the life of me figure out how this works. :?: Would anybody be kind enough to break this methodology down with a specific example so I can see what I'm doing wrong?

Thank you!
avatar
udini
Joined: 23 Jun 2010
Last visit: 24 Mar 2026
Posts: 1
Own Kudos:
1
 [1]
Given Kudos: 1
Posts: 1
Kudos: 1
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
@BeeSkool
Consider the number 273 ,
if you want to apply the rule
Quote:
7: Double the ones digit and subtract the last number from the remaining digits. If difference divisible by 7, True
then you have to
- double the ones digit : 2 x 3 =6
- subtract 6 from the number formed by the remaing digits ( = 27) : 27 -6 = 21

21 is divisible by 7 => 273 is divisible too
User avatar
BeeSkool
Joined: 14 Jun 2010
Last visit: 16 Jan 2012
Posts: 52
Own Kudos:
Given Kudos: 10
Posts: 52
Kudos: 1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
udini
@BeeSkool
Consider the number 273 ,
if you want to apply the rule
Quote:
7: Double the ones digit and subtract the last number from the remaining digits. If difference divisible by 7, True
then you have to
- double the ones digit : 2 x 3 =6
- subtract 6 from the number formed by the remaing digits ( = 27) : 27 -6 = 21

21 is divisible by 7 => 273 is divisible too



Awesome thanks! :-D
avatar
rsvaishu
Joined: 28 Jul 2010
Last visit: 13 Oct 2010
Posts: 1
Posts: 1
Kudos: 0
Kudos
Add Kudos
Bookmarks
Bookmark this Post
amazing for 7 and 11 properties and thanks for sharing it
User avatar
Robiou
Joined: 30 Sep 2010
Last visit: 22 Jan 2011
Posts: 24
Own Kudos:
Given Kudos: 1
Status:What to know what someone's dream looks like? Observe a large pile of GMAT books. (c)
GPA: 3.72
Posts: 24
Kudos: 15
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bah my post got deleted. Thanks for the table. By the way, on page 244 Kaplan Premier they—incorrectly—state that, "...you can combine these rules above with factorization tom figure out whether a number is divisible by other numbers." the example given is that 8184 is divisible by 44 because it is divisible by (4 and 11). While this may be true in this case, it should advise that you use prime factorization.

For example, 36 is divisible by both 4 and 2, yet it is not divisible by 8. Rather, it should be divisible by 2 three times.

Posted from GMAT ToolKit
User avatar
laurapv
Joined: 22 Jun 2010
Last visit: 10 Mar 2011
Posts: 12
Given Kudos: 4
Location: Dominican Republic
Schools:Rochester Institute of Technology
GPA: 3.84
Posts: 12
Kudos: 0
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Awesome, the MGMAT Number Properties didn't list the properties for 7,11, 12 and 15.
User avatar
PadawanOfTheGMAT
Joined: 31 Mar 2010
Last visit: 30 May 2013
Posts: 379
Own Kudos:
Given Kudos: 26
Location: Europe
Posts: 379
Kudos: 72
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Great addition to MGMAT Number Properties.
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,965
Own Kudos:
Posts: 38,965
Kudos: 1,117
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.
Moderators:
Math Expert
109782 posts
Tuck School Moderator
853 posts