NEW HERE? LEARN MORE
closeclose
Last visit was: 26 Apr 2024, 11:43 It is currently 26 Apr 2024, 11:43
Decision Tracker
My Rewards
New posts
New comers' posts

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

Which of the following CANNOT be the least common multiple of two posi

SORT BY:
Date
Kudos
Tags:
Find Similar Topics 
Show Tags
Hide Tags
User avatar
Gmatdecoder
Intern
Intern
Joined: 23 Nov 2014
Posts: 26
Own Kudos [?]: 154 [15]
Given Kudos: 4
Send PM
Which of the following CANNOT be the least common multiple of two posi [#permalink] New post   Updated on: 23 May 2015, 08:23
15
Bookmarks
00:00
A
B
C
D
E

Difficulty:

35% (medium)

Question Stats:

57% (00:55) correct 43% (00:54) wrong based on 215 sessions
Hide Show timer Statistics
Which of the following CANNOT be the least common multiple of two positive integers x and y?

(A) 1
(B) x
(C) y
(D) xy/2
(E) 2xy
ShowHide Answer
Official Answer
E

Originally posted by Gmatdecoder on 23 May 2015, 08:17.
Last edited by Bunuel on 23 May 2015, 08:23, edited 1 time in total.
Edited the question.
User avatar
L
Bunuel
Math Expert
Joined: 02 Sep 2009
Posts: 92948
Own Kudos [?]: 619221 [2]
Given Kudos: 81609
Send PM
CAT Tests Forum Quiz Mode
Re: Which of the following CANNOT be the least common multiple of two posi [#permalink] New post   23 May 2015, 08:25
2
Bookmarks
Expert Reply
Gmatdecoder wrote:
Which of the following CANNOT be the least common multiple of two positive integers x and y?

(A) 1
(B) x
(C) y
(D) xy/2
(E) 2xy


Similar questions to practice:
which-of-the-following-cannot-be-the-least-common-multiple-of-two-posi-181173.html?fl=similar
which-of-the-following-cannot-be-the-greatest-common-divisor-108865.html
which-of-the-following-cannot-be-the-least-common-multiple-167145.html
User avatar
Gmatdecoder
Intern
Intern
Joined: 23 Nov 2014
Posts: 26
Own Kudos [?]: 154 [0]
Given Kudos: 4
Send PM
Re: Which of the following CANNOT be the least common multiple of two posi [#permalink] New post   23 May 2015, 08:29
I tried to search this one but could'nt find. Please post a solution to this one as I am in doubt regarding OA
User avatar
Lucky2783
Senior Manager
Senior Manager
Joined: 07 Aug 2011
Posts: 425
Own Kudos [?]: 1752 [4]
Given Kudos: 75
Concentration: International Business, Technology
GMAT 1: 630 Q49 V27
Send PM
GMAT ToolKit User
Which of the following CANNOT be the least common multiple of two posi [#permalink] New post   23 May 2015, 09:58
1
Kudos
3
Bookmarks
Gmatdecoder wrote:
Which of the following CANNOT be the least common multiple of two positive integers x and y?

(A) 1
(B) x
(C) y
(D) xy/2
(E) 2xy



(A) 1 if x=y=1 , LCM=1
(B) x if x=k*y where k is a integer, then lcm(x,y) = x
(C) y if y=k*x where k is a integer, then lcm(x,y) = y
(D) xy/2 if x=\(2*P_1\) and y=\(2*P_2\) where \(P_1 , P_2\) are prime numbers, then LCM(x,y) = \(2*P_1*P_2\) = \(\frac{X*Y}{2}\)
(E) 2xy well, the answer for this question was this option straightforward . if there is something common between x and y then that would have been LCM but if there is nothing common between x and y , then the first multiple of X and Y will be \(X*Y\) and not \(2*X*Y\)
User avatar
L
EMPOWERgmatRichC
GMAT Club Legend
GMAT Club Legend
Joined: 19 Dec 2014
Status:GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Posts: 21846
Own Kudos [?]: 11668 [2]
Given Kudos: 450
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: Q170 V170
Send PM
Re: Which of the following CANNOT be the least common multiple of two posi [#permalink] New post   23 May 2015, 11:37
2
Kudos
Expert Reply
Hi Gmatdecoder,

You can approach this question by TESTing VALUES and eliminating answer choices...

We're told that X and Y are POSITIVE INTEGERS. We're asked which of the answer choices CANNOT be the least common multiple (LCM) of X and Y?

IF....
X = Y = 1
the LCM = 1
Eliminate Answer A

IF....
X = 2, Y = 1
The LCM = 2 = X
Eliminate Answer B

IF....
X = 1, Y = 2
The LCM = 2 = Y
Eliminate Answer C

IF....
X = Y = 2
the LCM = 2
Eliminate Answer D

There's only one answer left....

Final Answer:
Show Spoiler
E


GMAT assassins aren't born, they're made,
Rich
User avatar
L
EgmatQuantExpert
e-GMAT Representative
Joined: 04 Jan 2015
Posts: 3726
Own Kudos [?]: 16844 [4]
Given Kudos: 165
Send PM
Re: Which of the following CANNOT be the least common multiple of two posi [#permalink] New post   23 May 2015, 21:32
2
Kudos
2
Bookmarks
Expert Reply
Hi Gmatdecoder,

This question could have been easily solved had you been mindful of the constraints on values of LCM. Take note of the range of values of LCM of a set of numbers:

Magnitude of the largest integer of the set <= LCM of a set of integers<= Product of magnitude of all integers in the set

As you would see here that LCM of two numbers x and y can take maximum value of xy. Hence anything greater than xy will not be the possible value of LCM i.e. LCM(x, y) can't take a value of 2xy.

Want to know how is this range calculated and other such important points on LCM-GCD, go through our article 3 Deadly Mistakes you must avoid in LCM-GCD questions

Hope this helps :)

Regards
Harsh
avatar
B
pakasaip
Intern
Intern
Joined: 26 Feb 2015
Posts: 18
Own Kudos [?]: 7 [0]
Given Kudos: 76
Location: Thailand
Concentration: Entrepreneurship, Strategy
Schools: Anderson '20 (D) Ross '20 (D) Haas '20 (D) HEC Sept 2018 Intake (A) Duke '20 (WL) Kellogg '20 (D)
GMAT 1: 630 Q49 V27
GMAT 2: 680 Q48 V34
GPA: 2.92
WE:Supply Chain Management (Manufacturing)
Send PM
Re: Which of the following CANNOT be the least common multiple of two posi [#permalink] New post   12 Nov 2016, 02:21
Gmatdecoder wrote:
Which of the following CANNOT be the least common multiple of two positive integers x and y?

(A) 1
(B) x
(C) y
(D) xy/2
(E) 2xy


if GMAT mentions 2 variables, x and y, is it always possible that they can be the same integer (x=y).
In this question, I think that x and y must be 2 different integers, so I eliminated choice A
User avatar
bumpbot
Non-Human User
Joined: 09 Sep 2013
Posts: 32688
Own Kudos [?]: 822 [0]
Given Kudos: 0
Send PM
Re: Which of the following CANNOT be the least common multiple of two posi [#permalink] New post   26 Sep 2023, 05:45
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.
GMAT Club Bot
gmatclubot
Re: Which of the following CANNOT be the least common multiple of two posi [#permalink]
26 Sep 2023, 05:45
Moderators:
Bunuel
Math Expert
92948 posts
yashikaaggarwal
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions