It is currently 23 Feb 2018, 02:47

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# If x and y are both prime, is xy = 323?

Author Message
TAGS:

### Hide Tags

Intern
Joined: 24 Dec 2012
Posts: 26
Concentration: Entrepreneurship, Social Entrepreneurship
WE: Design (Computer Software)
If x and y are both prime, is xy = 323? [#permalink]

### Show Tags

23 Apr 2014, 07:36
14
This post was
BOOKMARKED
00:00

Difficulty:

85% (hard)

Question Stats:

42% (01:02) correct 58% (00:47) wrong based on 364 sessions

### HideShow timer Statistics

If x and y are both prime, is xy = 323?

(1) x is the first prime after 18.
(2) y is the last prime before 180.
[Reveal] Spoiler: OA
Current Student
Joined: 09 Mar 2014
Posts: 53
Location: India
Concentration: General Management, Operations
GMAT 1: 760 Q50 V42
GPA: 3.2
WE: Engineering (Energy and Utilities)
Re: If x and y are both prime, is xy = 323? [#permalink]

### Show Tags

23 Apr 2014, 08:51
3
KUDOS
1
This post was
BOOKMARKED
tusharGupta1 wrote:
If x and y are both prime, is xy = 323?

(1) x is the first prime after 18.
(2) y is the last prime before 180.

323 = 19 x 17. There are only four factors of 323...1, 17, 19, 323.

Statement 1: x is the first prime after 18. It means X=19. For xy = 323, y should be 17. But y can take any prime value ....2, 3, 5 etc. Not sufficient

Statement 2: y is the last prime before 180. It means y=179. Now x can take any prime value but product of 179 and any other number cannot be 323. Therefor, xy cannot be 323. Sufficient

Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 7955
Location: Pune, India
Re: If x and y are both prime, is xy = 323? [#permalink]

### Show Tags

23 Apr 2014, 19:55
2
KUDOS
Expert's post
1
This post was
BOOKMARKED
tusharGupta1 wrote:
If x and y are both prime, is xy = 323?

(1) x is the first prime after 18.
(2) y is the last prime before 180.

You have x and y are prime. You need to find whether xy = 323.

(1) x is the first prime after 18.

This means x is 19. But what is y? We don't know. So should we move on right away that this statement alone is not sufficient? No. What if 19 is not a factor of 323? Since both x and y are integers, if 19 were not a factor of 323, it would be sufficient to say that xy is not 323.
323/19 = 17. So if y is 17, xy will be 323. If y is any other value, xy will not be 323.
Not sufficient alone.

(2) y is the last prime before 180.
We don't need to find the last prime before 180 as long as we know that it would be 179 or 173 etc. We don't really need to find it exactly. What we do know is that last prime before 180 is certainly not 19. y is something like 179/173 etc and since 323 does not have 2 as a factor, xy will certainly not be 323. Hence this statement alone is sufficient to say that xy is NOT 323.

_________________

Karishma
Veritas Prep | GMAT Instructor
My Blog

Get started with Veritas Prep GMAT On Demand for \$199

Veritas Prep Reviews

Senior Manager
Joined: 31 Jul 2017
Posts: 298
Location: Malaysia
WE: Consulting (Energy and Utilities)
Re: If x and y are both prime, is xy = 323? [#permalink]

### Show Tags

31 Jan 2018, 18:38
tusharGupta1 wrote:
If x and y are both prime, is xy = 323?

(1) x is the first prime after 18.
(2) y is the last prime before 180.

Statement I:

$$x = 19$$, y can be 2,3,5,7,11,17,.... etc. So, Insufficient.

Statement II:

$$y = 179$$. When we factorize $$323$$ we have $$323 = 17*19$$. So, one number has to be either of them. But as this statement one number is 179. Hence, their product wont be equal to 323.

So, Sufficient.
_________________

If my Post helps you in Gaining Knowledge, Help me with KUDOS.. !!

Senior Manager
Joined: 07 Jul 2012
Posts: 299
Location: India
Concentration: Finance
Re: If x and y are both prime, is xy = 323? [#permalink]

### Show Tags

31 Jan 2018, 22:41
Factors of 323 are: {1, 17 ,19 ,323}

(1) x= 19 and and y can be any prime number{2,3,5,7,11,13,17...}
If x= 19 and y=17 then [Yes]
If x=19 and y= 2 then [No]
We need confirm answer either yes or no [Insuff]

(2)Y=180 and x can be any prime number{2,3,5,7,11,13,17....}
In all these cases, product of xy can never be 323

So we have confirmed no answer. [Suff]

_________________

Kindly hit kudos if my post helps!

Re: If x and y are both prime, is xy = 323?   [#permalink] 31 Jan 2018, 22:41
Display posts from previous: Sort by