Last visit was: 19 Nov 2025, 19:52 It is currently 19 Nov 2025, 19:52
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
enigma123
Joined: 25 Jun 2011
Last visit: 16 Mar 2016
Posts: 392
Own Kudos:
19,303
 [48]
Given Kudos: 217
Status:Finally Done. Admitted in Kellogg for 2015 intake
Location: United Kingdom
Concentration: International Business, Strategy
GMAT 1: 730 Q49 V45
GPA: 2.9
WE:Information Technology (Consulting)
GMAT 1: 730 Q49 V45
Posts: 392
Kudos: 19,303
 [48]
7
Kudos
Add Kudos
41
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 19 Nov 2025
Posts: 105,390
Own Kudos:
Given Kudos: 99,977
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 105,390
Kudos: 778,381
 [34]
16
Kudos
Add Kudos
18
Bookmarks
Bookmark this Post
User avatar
EgmatQuantExpert
User avatar
e-GMAT Representative
Joined: 04 Jan 2015
Last visit: 02 Apr 2024
Posts: 3,663
Own Kudos:
20,167
 [5]
Given Kudos: 165
Expert
Expert reply
Posts: 3,663
Kudos: 20,167
 [5]
4
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
General Discussion
User avatar
enigma123
Joined: 25 Jun 2011
Last visit: 16 Mar 2016
Posts: 392
Own Kudos:
19,303
 [1]
Given Kudos: 217
Status:Finally Done. Admitted in Kellogg for 2015 intake
Location: United Kingdom
Concentration: International Business, Strategy
GMAT 1: 730 Q49 V45
GPA: 2.9
WE:Information Technology (Consulting)
GMAT 1: 730 Q49 V45
Posts: 392
Kudos: 19,303
 [1]
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
Thanks very much buddy for shedding light on concept of ZERO.
User avatar
prashantrchawla
Joined: 02 Nov 2013
Last visit: 10 Feb 2017
Posts: 60
Own Kudos:
Given Kudos: 10
Location: India
Posts: 60
Kudos: 31
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Let's take x=30, in this case,
1. A Will be sufficient. However 30-1 is 29 is not a factor of 104.
2. 27 is also not divisible by 30. Not sufficient.

Hence, In this case is the answer E. Can anybody answer my doubt.
User avatar
abhimahna
User avatar
Board of Directors
Joined: 18 Jul 2015
Last visit: 06 Jul 2024
Posts: 3,514
Own Kudos:
Given Kudos: 346
Status:Emory Goizueta Alum
Products:
Expert
Expert reply
Posts: 3,514
Kudos: 5,728
Kudos
Add Kudos
Bookmarks
Bookmark this Post
prashantrchawla
Let's take x=30, in this case,
1. A Will be sufficient. However 30-1 is 29 is not a factor of 104.
2. 27 is also not divisible by 30. Not sufficient.

Hence, In this case is the answer E. Can anybody answer my doubt.

I am not sure what you are trying to do here.

for statement 1 : you are considering only one value of x, which is making your case sufficient. Take x =3 and x = 6, you will get 104 divisible for x-1 = 2 but not for x-1 = 5.

Hence, it is Insufficient.

Statement 2 : We are given 27 is divisible by x. It means x is a factor of 27. The factors could be 1,3,9 and 27.

Divide 104 by each of (x-1) as 0, 2,8 and 26. You will find 104 divisible by all but 0. hence, insufficient.

On combining, we know that x cannot be 0. Hence, Answer C.
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 19 Nov 2025
Posts: 105,390
Own Kudos:
Given Kudos: 99,977
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 105,390
Kudos: 778,381
Kudos
Add Kudos
Bookmarks
Bookmark this Post
prashantrchawla
Let's take x=30, in this case,
1. A Will be sufficient. However 30-1 is 29 is not a factor of 104.
2. 27 is also not divisible by 30. Not sufficient.

Hence, In this case is the answer E. Can anybody answer my doubt.

Your logic there is not clear. Why do you take x as 30? You cannot arbitrarily take x to be 30 and work with this value only. Also, how is the first statement sufficient? If x is 3, then x-1=2 and the answer would be YES but if x is 3,000 then the answer would be NO.

Please re-read the solutions above.
User avatar
amanvermagmat
User avatar
Retired Moderator
Joined: 22 Aug 2013
Last visit: 28 Mar 2025
Posts: 1,148
Own Kudos:
Given Kudos: 480
Location: India
Posts: 1,148
Kudos: 2,855
Kudos
Add Kudos
Bookmarks
Bookmark this Post
enigma123
If x is a positive integer, is x – 1 a factor of 104?

(1) x is divisible by 3.
(2) 27 is divisible by x.

Lets look at the prime factorisation of 104: 2^3 * 13
Thus factors of 104 = 1, 2, 4, 8, 13, 26, 52, 104
We are asked whether x-1 is one of these 8 integers, OR IS x one of these: 2, 3, 5, 9, 14, 27, 53, 105

(1) x is divisible by 3, so x could be any multiple of 3 like 9 or 27 or 54. Insufficient.

(2) 27 is divisible by x, so x is a factor of 27. Now factors of 27 are: 1, 3, 9, 27.
If x is 1, then x-1 is 0 and thus NOT a factor of 104, but if x is 3 or 9 or 27, then x-1 will take values as 2 or 8 or 26 respectively, and thus BE a factor of 104.
So Insufficient.

Combining the two statements, x has to be a multiple of 3, yet a factor of 27 also. So x could be either 3 or 9 or 27. For each of these cases, x-1 will be a factor of 104, as explained in statement 2. Sufficient. Hence C answer
User avatar
NikhilJose
Joined: 19 Nov 2020
Last visit: 30 Nov 2021
Posts: 22
Own Kudos:
Given Kudos: 27
Location: India
GMAT 1: 710 Q49 V38
GMAT 1: 710 Q49 V38
Posts: 22
Kudos: 3
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hi Bunuel,
Should we consider division by zero for the GMAT?

I disregarded 1 for this question and hence got B.

Thanks in advance for your response.

Nik
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 19 Nov 2025
Posts: 105,390
Own Kudos:
Given Kudos: 99,977
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 105,390
Kudos: 778,381
Kudos
Add Kudos
Bookmarks
Bookmark this Post
NikhilJose
Hi Bunuel,
Should we consider division by zero for the GMAT?

I disregarded 1 for this question and hence got B.

Thanks in advance for your response.

Nik

We are told that x is a positive integer, so x cannot be 0.
User avatar
Kinshook
User avatar
Major Poster
Joined: 03 Jun 2019
Last visit: 19 Nov 2025
Posts: 5,794
Own Kudos:
Given Kudos: 161
Location: India
GMAT 1: 690 Q50 V34
WE:Engineering (Transportation)
Products:
GMAT 1: 690 Q50 V34
Posts: 5,794
Kudos: 5,514
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Asked: If x is a positive integer, is x – 1 a factor of 104?

104 = 2*2*2*13 = 2^3*13

(1) x is divisible by 3.
If x = 3; x-1 = 2 is a factor of 104
But if x=6; x-1 = 5 is NOT a factor of 104
NOT SUFFICIENT

(2) 27 is divisible by x.
27 = 3^3
x = {1,3,9,27}
x - 1 = {0,2,8,26}
27 is divisible by {2,8,26} but NOT divisible by 0.
NOT SUFFICIENT

(1) + (2)
(1) x is divisible by 3.
(2) 27 is divisible by x.
x = {3,9,27}
x - 1 = {2,8,26}
104 is divisible by {2,8,26}
SUFFICIENT

IMO C
User avatar
Kriti1055
Joined: 13 Apr 2021
Last visit: 20 Feb 2024
Posts: 7
Own Kudos:
Given Kudos: 93
Posts: 7
Kudos: 6
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hi Kinshook, Bunuel

I am a little confused here. Request your help.

Should we consider 0 (where x=1) a factor since anything divided by zero is undefined?

Knowing that 0 cannot be a factor of any number, is it not possible to automatically discard 1 as of the possibilities and keep the remaining-27,3,9, making St. B sufficient to be the correct answer?
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 19 Nov 2025
Posts: 105,390
Own Kudos:
Given Kudos: 99,977
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 105,390
Kudos: 778,381
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Kriti1055
Hi Kinshook, Bunuel

I am a little confused here. Request your help.

Should we consider 0 (where x=1) a factor since anything divided by zero is undefined?

Knowing that 0 cannot be a factor of any number, is it not possible to automatically discard 1 as of the possibilities and keep the remaining-27,3,9, making St. B sufficient to answer the correct answer?

(2) says: 27 is divisible by x. So, x can be 1, 3, 9, and 27.

The question asks: is x – 1 a factor of 104?

If x = 1, then the question becomes: is 0 a factor of 104? The answer to this question is NO (0 is NOT a factor of 104).

So, there is no problem for x to be 1, it just gives a NO answer to the question.

Hope it helps.
User avatar
KarishmaB
Joined: 16 Oct 2010
Last visit: 19 Nov 2025
Posts: 16,267
Own Kudos:
77,001
 [1]
Given Kudos: 482
Location: Pune, India
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 16,267
Kudos: 77,001
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
enigma123
If x is a positive integer, is x – 1 a factor of 104?

(1) x is divisible by 3.
(2) 27 is divisible by x.

104 = 2 * 2 * 2 * 13
So factors of 104 would be combinations of these... 1, 2, 4, 8, 26, etc
For (x-1) to be a factor of 104, it should be one of these.

(1) x is divisible by 3.

x could be 3 so (x - 1) would be 2 - a factor of 104
x could be 6 so (x-1) would be 5 - not a factor of 104
Not sufficient

(2) 27 is divisible by x.

So x can be only 1 or 3 or 9 or 27

x could be 1 so (x - 1) = 0 - not a factor of 104
x could be 3 so (x - 1) = 2 - a factor of 104
Not Sufficient

Using both statements, we see that x can be 3 or 9 or 27 only. So (x-1) will be 2 or 8 or 26. Each one of these is a factor of 104.
Hence, sufficient. (x-1) is a factor of 104.

Answer (C)

For more on factors, check this video and these posts: https://youtu.be/DxIH8rjhpKY
https://anaprep.com/number-properties-f ... -a-number/
https://anaprep.com/number-properties-r ... e-factors/
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,589
Own Kudos:
Posts: 38,589
Kudos: 1,079
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
Moderators:
Math Expert
105390 posts
496 posts