It is currently 21 Jan 2018, 14:13

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

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

What is the value of positive integer x?

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Expert Post
1 KUDOS received
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 43348

Kudos [?]: 139706 [1], given: 12794

What is the value of positive integer x? [#permalink]

Show Tags

New post 22 Apr 2017, 07:10
1
This post received
KUDOS
Expert's post
6
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  85% (hard)

Question Stats:

48% (01:25) correct 52% (01:27) wrong based on 211 sessions

HideShow timer Statistics

Kudos [?]: 139706 [1], given: 12794

2 KUDOS received
Director
Director
User avatar
P
Joined: 05 Mar 2015
Posts: 962

Kudos [?]: 311 [2], given: 41

What is the value of positive integer x? [#permalink]

Show Tags

New post 22 Apr 2017, 07:28
2
This post received
KUDOS
Bunuel wrote:
What is the value of positive integer x?

(1) x<45
(2) 45 is a factor of 4x^2



(1) clearly insuff

(2) x can be 45 or 90

combining we get x =15 or 3*5*2 =30 ( which is <45)

insuff

Ans E

Last edited by rohit8865 on 22 Apr 2017, 08:45, edited 1 time in total.

Kudos [?]: 311 [2], given: 41

Intern
Intern
avatar
B
Joined: 10 Mar 2015
Posts: 11

Kudos [?]: [0], given: 9

Re: What is the value of positive integer x? [#permalink]

Show Tags

New post 22 Apr 2017, 07:56
rohit8865 wrote:
Bunuel wrote:
What is the value of positive integer x?

(1) x<45
(2) 45 is a factor of 4x^2



(1) clearly insuff

(2) x can be 45 or 90

combining we get x =15(3*5 which is <45)

suff

Ans C


I think it's E
x could be 15 or 30, both <45

Is it?

Kudos [?]: [0], given: 9

Intern
Intern
avatar
Joined: 13 Apr 2017
Posts: 1

Kudos [?]: 0 [0], given: 3

Location: India
Schools: IIMA (A)
GMAT 1: 740 Q50 V40
GPA: 3.25
Re: What is the value of positive integer x? [#permalink]

Show Tags

New post 22 Apr 2017, 08:06
rohit8865 wrote:
Bunuel wrote:
What is the value of positive integer x?

(1) x<45
(2) 45 is a factor of 4x^2



(1) clearly insuff

(2) x can be 45 or 90

combining we get x =15(3*5 which is <45)

suff

Ans C


What if x=30? It suffices both conditions A and B. Also it is the only value other than 15 which fits both criteria.

Kudos [?]: 0 [0], given: 3

1 KUDOS received
Director
Director
User avatar
P
Joined: 05 Mar 2015
Posts: 962

Kudos [?]: 311 [1], given: 41

What is the value of positive integer x? [#permalink]

Show Tags

New post 22 Apr 2017, 08:46
1
This post received
KUDOS
Jargalan wrote:
rohit8865 wrote:
Bunuel wrote:
What is the value of positive integer x?

(1) x<45
(2) 45 is a factor of 4x^2



(1) clearly insuff

(2) x can be 45 or 90

combining we get x =15(3*5 which is <45)

suff

Ans C


I think it's E
x could be 15 or 30, both <45

Is it?



Yes of course
you are correct
post edited!!!!!

thanks

Kudos [?]: 311 [1], given: 41

1 KUDOS received
Manager
Manager
avatar
B
Joined: 02 Feb 2016
Posts: 89

Kudos [?]: 10 [1], given: 40

GMAT 1: 690 Q43 V41
Re: What is the value of positive integer x? [#permalink]

Show Tags

New post 01 Aug 2017, 11:13
1
This post received
KUDOS
How are we getting x=30 by combining both statements?

Kudos [?]: 10 [1], given: 40

Board of Directors
User avatar
V
Status: Aiming MBA
Joined: 18 Jul 2015
Posts: 3005

Kudos [?]: 1071 [0], given: 74

Location: India
Concentration: Healthcare, Technology
GPA: 3.65
WE: Information Technology (Health Care)
Premium Member Reviews Badge
Re: What is the value of positive integer x? [#permalink]

Show Tags

New post 03 Aug 2017, 05:02
TheMastermind wrote:
How are we getting x=30 by combining both statements?


Hi TheMastermind ,

For 45 to be factor of 4x^2 , I need atleast two 3s and one 5 in 4x^2.

Now, this could be possible x = 15. Its square will give me what I want.

Similarly, x could be 30 , again its square will give me what I want. Since we have two possible values of x, answer is E.

Does that make sense?
_________________

How I improved from V21 to V40! ?


How to use this forum in THE BEST way?

Kudos [?]: 1071 [0], given: 74

Senior Manager
Senior Manager
avatar
S
Joined: 15 Jan 2017
Posts: 360

Kudos [?]: 8 [0], given: 830

CAT Tests
Re: What is the value of positive integer x? [#permalink]

Show Tags

New post 05 Nov 2017, 10:04
Tried by plugging in numbers only.

1) St x < 45--> clearly NS
2) 4x ^2/ 45 = no remainder. just by hit and trial (factors of 9,5,3) --> 4 *22500/45 (no remainder) and 4*900/45 (no remainder).
x = 30 or 15. NS

1) 2) Both giving multiple values of x. So insufficient

Kudos [?]: 8 [0], given: 830

Intern
Intern
avatar
B
Joined: 02 Sep 2017
Posts: 10

Kudos [?]: 0 [0], given: 37

Reviews Badge CAT Tests
What is the value of positive integer x? [#permalink]

Show Tags

New post 07 Nov 2017, 03:50
ok people.

So, A is insufficient. B is insufficient.

However, combining the two statements, you get 4x^2 = 45I
The question already states that x is a positive integer. Therefore, x^2 also HAS to be a positive integer.
THerefore, x^2 = 45I/4 = an integer

So, x has to be an even integer.

So, out of 15 and 30, only 30 suffices.

Hence C.

YAHOOOO

Kudos [?]: 0 [0], given: 37

Manager
Manager
avatar
S
Joined: 10 Dec 2011
Posts: 110

Kudos [?]: 40 [0], given: 93

Location: India
Concentration: Finance, Economics
GMAT Date: 09-28-2012
WE: Accounting (Manufacturing)
What is the value of positive integer x? [#permalink]

Show Tags

New post 11 Nov 2017, 06:52
Good one. X=30 or 15 because 45 = 3*3*5. Even if X has one 5 & 3, it can be divided by 45 (5*3*3) if it is squared. X^2 = 5*5*3*3. Thus, The least possible value of X = 5*3=15. And it is less than 45 according to I. Therefore answer = 15. Wait, another possible value is 30 which also fits the equation. Hence, E.

Kudos [?]: 40 [0], given: 93

Intern
Intern
avatar
B
Joined: 27 Apr 2015
Posts: 26

Kudos [?]: 3 [0], given: 131

GMAT 1: 370 Q29 V13
Reviews Badge
Re: What is the value of positive integer x? [#permalink]

Show Tags

New post 05 Jan 2018, 07:36
2
This post was
BOOKMARKED
Bunuel wrote:
What is the value of positive integer x?

(1) x<45
(2) 45 is a factor of 4x^2



Given x>0 & Integer

Find Value of 'x'

Statement 1 x<45
=> So x=1,2,3,4....44
=> Many Values of 'x'. Therefore INSUFFICIENT

Statement 2 45 is a factor of \(4x^2\)
=> So \(4x^2\) is a multiple of 45
=> OR \(4x^2=45*k\) ----- 'k' some constant
=> OR \(x^2=\frac{(45*k)}{4}\)

=> For 'x' to be Positive Integer \(\frac{(45*k)}{4}\) should be a PERFECT SQUARE & Integer.

=> Now Prime Factorising 45 we have \(45=3^2*5\)

=> Therefore 'k' should be \((4*5)\) or \((4*5*2^2)\) or \((4*5*2^2*3^3)\) or \((4*5^3*2^2)\) and so on

=> Thus \(x^2\)=\(\frac{(45*4*5)}{4}\) or \(\frac{(45*4*5*2^2)}{4}\) or \(\frac{(45*4*5*2^2*3^2)}{4}\) or \(\frac{(45*4*5^3*2^2)}{4}\) and so on

=> OR x=15,30,90,150..... so on
=> Many Values of 'x'. Therefore INSUFFICIENT

BOTH Stat 1 & 2
=> x=15,30,90,150..... so on ---- from Stat 2
=> x=15,30 --------------- constraint of Stat 1
=> AGAIN 'x' has 2 values. Therefore INSUFFICIENT

Therefore 'E'

Thanks
Dinesh

Kudos [?]: 3 [0], given: 131

Re: What is the value of positive integer x?   [#permalink] 05 Jan 2018, 07:36
Display posts from previous: Sort by

What is the value of positive integer x?

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.