Last visit was: 14 Dec 2024, 16:59 It is currently 14 Dec 2024, 16:59
Home
GMAT
Messages
Tests
Schools
Reviews
Social
Chat
My Profile
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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
User avatar
stonecold
User avatar
Joined: 12 Aug 2015
Last visit: 09 Apr 2024
Posts: 2,261
Own Kudos:
3,300
 []
Given Kudos: 893
Schools: Boston U '20 (M)
GRE 1: Q169 V154
Schools: Boston U '20 (M)
GRE 1: Q169 V154
Posts: 2,261
Kudos: 3,300
 []
What is the value of integer N if 2,3,5 are the only prime factors of Updated on: 22 Nov 2016, 03:19
Originally posted by stonecold on 22 Nov 2016, 03:15.
Last edited by Bunuel on 22 Nov 2016, 03:19, edited 1 time in total.
Renamed the topic and edited the question.
Kudos
Add Kudos
3
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
E
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

15% (low)

Question Stats:

70% (00:41) correct 30% (00:46) wrong based on 118 sessions

History

Date
Time
Result
Not Attempted Yet
What is the value of integer N if 2,3,5 are the only prime factors of N

A) 30
B) 60
C) 90
D) 120
E) cannot be determined
ShowHide Answer
Official Answer
E
User avatar
broall
User avatar
Retired Moderator
Joined: 10 Oct 2016
Last visit: 07 Apr 2021
Posts: 1,141
Own Kudos:
6,616
Given Kudos: 65
Status:Long way to go!
Location: Viet Nam
Posts: 1,141
Kudos: 6,616
What is the value of integer N if 2,3,5 are the only prime factors of 22 Nov 2016, 03:35
Kudos
Add Kudos
Bookmarks
Bookmark this Post
stonecold
What is the value of integer N if 2,3,5 are the only prime factors of N

A) 30
B) 60
C) 90
D) 120
E) cannot be determined

\(N=2^x 3^y 5^z\). Since we cant know the values of x, y, z, the value of N can't be determined. Choice E.
User avatar
Abhishek009
User avatar
Board of Directors
Joined: 11 Jun 2011
Last visit: 02 Oct 2024
Posts: 6,014
Own Kudos:
4,952
Given Kudos: 463
Status:QA & VA Forum Moderator
Location: India
GPA: 3.5
WE:Business Development (Commercial Banking)
Posts: 6,014
Kudos: 4,952
What is the value of integer N if 2,3,5 are the only prime factors of 22 Nov 2016, 08:48
Kudos
Add Kudos
Bookmarks
Bookmark this Post
stonecold
What is the value of integer N if 2,3,5 are the only prime factors of N

A) 30
B) 60
C) 90
D) 120
E) cannot be determined

Greatest value of N will depend on the exponents of its factor...

Since, we do not know the exponents, answer will be (E) cannot be determined..
User avatar
stonecold
User avatar
Joined: 12 Aug 2015
Last visit: 09 Apr 2024
Posts: 2,261
Own Kudos:
3,300
 []
Given Kudos: 893
Schools: Boston U '20 (M)
GRE 1: Q169 V154
Schools: Boston U '20 (M)
GRE 1: Q169 V154
Posts: 2,261
Kudos: 3,300
 []
What is the value of integer N if 2,3,5 are the only prime factors of 07 Jan 2017, 17:31
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
There exist infinite numbers with the same set of primes.
Hence if are only given the prime factors of any integer and no other information is provided => We can never calculate the number.
E.g=> 2*3*5
2*3*5^100
2^100*3*5
Etc.
Hence E.
User avatar
Alexey1989x
User avatar
Joined: 05 Dec 2016
Last visit: 20 May 2023
Posts: 194
Own Kudos:
90
Given Kudos: 49
Concentration: Strategy, Finance
GMAT 1: 620 Q46 V29
GMAT 1: 620 Q46 V29
Posts: 194
Kudos: 90
What is the value of integer N if 2,3,5 are the only prime factors of 08 Jan 2017, 04:03
Kudos
Add Kudos
Bookmarks
Bookmark this Post
I do believe that such kind of questions should specify that power values of prime factors are unknown,as someone could think that it is ebqual to 1 by default.
User avatar
stonecold
User avatar
Joined: 12 Aug 2015
Last visit: 09 Apr 2024
Posts: 2,261
Own Kudos:
3,300
Given Kudos: 893
Schools: Boston U '20 (M)
GRE 1: Q169 V154
Schools: Boston U '20 (M)
GRE 1: Q169 V154
Posts: 2,261
Kudos: 3,300
What is the value of integer N if 2,3,5 are the only prime factors of 08 Jan 2017, 04:07
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Alexey1989x
I do believe that such kind of questions should specify that power values of prime factors are unknown,as someone could think that it is ebqual to 1 by default.
No.
Not at all.
The question need not specify anything.
Lets take an example ->
If 2,3,5 are the prime factors of n what is the value of n?

Here we cannot get n.
As there exist ∞ numbers with the same set of primes.


Regards
Stone Cold
User avatar
Abhishek009
User avatar
Board of Directors
Joined: 11 Jun 2011
Last visit: 02 Oct 2024
Posts: 6,014
Own Kudos:
4,952
Given Kudos: 463
Status:QA & VA Forum Moderator
Location: India
GPA: 3.5
WE:Business Development (Commercial Banking)
Posts: 6,014
Kudos: 4,952
What is the value of integer N if 2,3,5 are the only prime factors of 08 Jan 2017, 05:40
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Alexey1989x
I do believe that such kind of questions should specify that power values of prime factors are unknown,as someone could think that it is ebqual to 1 by default.

The presence of the option (E) None of the above is a clear indication that one needs to check all the possibilities carefully before marking an answer...

stonecold is correct " The question need not specify anything. " and expect us to find the correct answer ...

Hence, correct answer will always be (E)
User avatar
vishwash
User avatar
Joined: 20 Jun 2013
Last visit: 28 May 2022
Posts: 34
Own Kudos:
19
Given Kudos: 23
Location: India
Concentration: Economics, Finance
GMAT 1: 430 Q39 V25
GPA: 3.5
WE:Information Technology (Other)
GMAT 1: 430 Q39 V25
Posts: 34
Kudos: 19
What is the value of integer N if 2,3,5 are the only prime factors of 02 Apr 2017, 13:06
Kudos
Add Kudos
Bookmarks
Bookmark this Post
thanks stonecold for a beautifully crafted intricated question......... kudos to you..... thanks it help to strengthen your fundamentals .. thannks again
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 35,824
Own Kudos:
930
Posts: 35,824
Kudos: 930
What is the value of integer N if 2,3,5 are the only prime factors of 08 May 2022, 00:55
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.
Moderator:
Bunuel
Math Expert
97877 posts