If x and y are nonzero integers, is 18 a factor of xy^2?

Oldest

Best Reply

Author

Message

TAGS:

Director

Status: GMAT Learner

Joined: 14 Jul 2010

Posts: 672

Followers: 21

Kudos [?]: 108 [0], given: 31

If x and y are nonzero integers, is 18 a factor of xy^2? [#permalink]

13 Jan 2012, 09:49

00:00

Question Stats:

46% (01:48) correct

53% (01:30) wrong

based on 8 sessions

If x and y are nonzero integers, is 18 a factor of xy^2?

(1) x is a multiple of 54.
(2) y is a multiple of 6.

[Reveal] Spoiler:

I did A.
In case of option 2 y is a multiple of 6.
So y = 6, 12, 18 .......if y = 6, then the factors of 6 could is 2 & 3 but factors of 18 are 2, 3 & 3. Thus 18 Could be not a factor of xy^2.

What is the wrong with me?

[Reveal] Spoiler: OA

_________________

I am student of everyone-baten
Collections:-
PSof OG solved by GC members: http://gmatclub.com/forum/collection-ps-with-solution-from-gmatclub-110005.html
DS of OG solved by GC members: http://gmatclub.com/forum/collection-ds-with-solution-from-gmatclub-110004.html
100 GMAT PREP Quantitative collection http://gmatclub.com/forum/gmat-prep-problem-collections-114358.html
Collections of work/rate problems with solutions http://gmatclub.com/forum/collections-of-work-rate-problem-with-solutions-118919.html
Mixture problems in a file with best solutions: http://gmatclub.com/forum/mixture-problems-with-best-and-easy-solutions-all-together-124644.html

GMAT Club team member

Joined: 02 Sep 2009

Posts: 11611

Followers: 1801

Kudos [?]: 9596 [0], given: 829

Re: If x and y are nonzero integers [#permalink]

13 Jan 2012, 10:20

Baten80 wrote:

If x and y are nonzero integers, is 18 a factor of xy^2?
(1) x is a multiple of 54.
(2) y is a multiple of 6.

I did A.
In case of option 2 y is a multiple of 6.
So y = 6, 12, 18 .......if y = 6, then the factors of 6 could is 2 & 3 but factors of 18 are 2, 3 & 3. Thus 18 Could be not a factor of xy^2.

What is the wrong with me?

If x and y are nonzero integers, is 18 a factor of xy^2?

(1) x is a multiple of 54 --> x is a multiple of 18 as well (54=18*3) --> xy^2 is also a multiple of 18. Sufficient.

(2) y is a multiple of 6 --> y^2 is a multiple of 6^2=36 --> y^2 is a multiple of 18 as well (36=18*2) --> the same here: as y^2 is a multiple of 18 then xy^2 is also a multiple of 18. Sufficient.

Answer: D.
_________________

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. NEW!!!

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set. NEW!!!

What are GMAT Club Tests?
25 extra-hard Quant Tests

Find out what's new at GMAT Club - latest features and updates

Director

Status: GMAT Learner

Joined: 14 Jul 2010

Posts: 672

Followers: 21

Kudos [?]: 108 [0], given: 31

Re: If x and y are nonzero integers [#permalink]

13 Jan 2012, 11:04

I considered y rather y^2
Thank u bunnuel
_________________

Manager

Joined: 29 Jul 2011

Posts: 113

Location: United States

Followers: 1

Kudos [?]: 21 [0], given: 6

Re: If x and y are nonzero integers [#permalink]

13 Jan 2012, 11:56

1. x=54 = 18 x 3. So, 18 is a factor of x -> 18 is a factor of xy^2. Suff
2. y=6 -> y^2 = 36 = 18x2 -> 18 is a factor of y^2 -> 18 is a factor of xy^2. Suff

D
_________________

I am the master of my fate. I am the captain of my soul.
Please consider giving +1 Kudos if deserved!

DS - If negative answer only, still sufficient. No need to find exact solution.
PS - Always look at the answers first
CR - Read the question stem first, hunt for conclusion
SC - Meaning first, Grammar second
RC - Mentally connect paragraphs as you proceed. Short = 2min, Long = 3-4 min

GMAT Club team member

Joined: 02 Sep 2009

Posts: 11611

Followers: 1801

Kudos [?]: 9596 [0], given: 829

Re: If x and y are nonzero integers, is 18 a factor of xy^2? [#permalink]

22 May 2013, 03:39

Bumping for review and further discussion.
_________________

Intern

Joined: 24 Apr 2013

Posts: 43

Schools: Duke '16

Followers: 0

Kudos [?]: 0 [0], given: 56

Re: If x and y are nonzero integers, is 18 a factor of xy^2? [#permalink]

22 May 2013, 14:40

I was actually thinking C cause they both can be used but wasnt sure if they could be used alone

Re: If x and y are nonzero integers, is 18 a factor of xy^2? [#permalink] 22 May 2013, 14:40

	Similar topics	Author	Replies	Last post
Similar Topics:	If x and y are nonzero integers, is x^y < y^x? A. x=y^2	nfa1rhp	3	29 Jul 2007, 11:11
	If x and y are nonzero integers, is 18 a factor of xy2? (1)	jet1445	4	31 Jul 2007, 09:50
	If xy=-6, what is xy(x + y)? 1) x - y = 5 2) x(y^2) = 18	sonibubu	7	29 Jan 2008, 18:12
	If x and y are positive integers, is x - y > (x+y)/2 ?	Economist	2	25 Oct 2009, 05:03
	If x and y are nonzero integers, is x/y an integer?	dzodzo85	3	03 Apr 2012, 01:41

If x and y are nonzero integers, is 18 a factor of xy^2?

Main navigation

GMAT Resources

Partners

MBA Resources

GMAT ® is a registered trademark of the Graduate Management Admission Council ® (GMAC ®). GMAT Club's website has not been reviewed or endorsed by GMAC.

GMAT Courses

Admissions Consulting

If x and y are nonzero integers, is 18 a factor of xy^2?

If x and y are nonzero integers, is 18 a factor of xy^2?

Main navigation

GMAT Resources

Partners

MBA Resources