If n is an integer, what is the greatest common divisor of 12 and n ?
(1) The product of 12 and n is 432.
(2) The greatest common divisor of 24 and n is 12.
GMAT Official Guide 2019 If n is an integer, what
This topic has expert replies
-
- Moderator
- Posts: 7187
- Joined: Thu Sep 07, 2017 4:43 pm
- Followed by:23 members
Timer
00:00
Your Answer
A
B
C
D
E
Global Stats
- GMATGuruNY
- GMAT Instructor
- Posts: 15539
- Joined: Tue May 25, 2010 12:04 pm
- Location: New York, NY
- Thanked: 13060 times
- Followed by:1906 members
- GMAT Score:790
Timer
00:00
Your Answer
A
B
C
D
E
Global Stats
Statement 1:BTGmoderatorDC wrote:If n is an integer, what is the greatest common divisor of 12 and n ?
(1) The product of 12 and n is 432.
(2) The greatest common divisor of 24 and n is 12.
12n = 432.
Since we can solve for n, the GCF of 12 and n can be determined.
SUFFICIENT.
Statement 2:
24 = 2*2*2*3.
Since the GCF of n and 24 is the blue product (12) without the red factor (2), n must be a multiple of 12 that does NOT include an additional factor of 2.
In other words:
n = 12a, where a is an ODD positive integer.
Options for n:
12*1, 12*3, 12*5, 12*7, 12*9...
In every case, the GCF of n and 12 is the value in green (12).
SUFFICIENT.
The correct answer is D.
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.
As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.
For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3
GMAT/MBA Expert
- Jeff@TargetTestPrep
- GMAT Instructor
- Posts: 1462
- Joined: Thu Apr 09, 2015 9:34 am
- Location: New York, NY
- Thanked: 39 times
- Followed by:22 members
Timer
00:00
Your Answer
A
B
C
D
E
Global Stats
We need to determine the greatest common divisor or the greatest common factor (GCF) of 12 and n. If we can determine the value of n, then we can determine the GCF of 12 and n.BTGmoderatorDC wrote:If n is an integer, what is the greatest common divisor of 12 and n ?
(1) The product of 12 and n is 432.
(2) The greatest common divisor of 24 and n is 12.
Statement One Alone:
The product of 12 and n is 432
Since 12n = 432, n = 432/12 = 36. So the GCF of 12 and 36 is 12.
Statement one alone is sufficient.
Statement Two Alone:
The greatest common divisor of 24 and n is 12.
Since the GCF of 24 and n is 12, that means n itself is a multiple of 12. Therefore, the GCF of 12 and n must be also 12.
Statement two is sufficient.
Answer: D
Jeffrey Miller
Head of GMAT Instruction
[email protected]
See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews