Last visit was: 18 May 2026, 01:01 It is currently 18 May 2026, 01:01
Home
Messages
Tests
Schools
Events
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
User avatar
combres
User avatar
Joined: 12 Jul 2007
Last visit: 20 Nov 2011
Posts: 44
Own Kudos:
59
Posts: 44
Kudos: 59
If x and y are positive integers, is x an even int? 1) 29 Oct 2007, 11:20
Kudos
Add Kudos
Bookmarks
Bookmark this Post
If x and y are positive integers, is x an even int?

1) x(y+5) is an even int
2) 6y^2 + 41y + 25 is even int


I can't seem to find a way for (2) to be an even integer no matter what I plug in and I think it is a waste of time to factor (2)

any ideas?



Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block below for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
User avatar
sevenplus
User avatar
Joined: 26 Sep 2007
Last visit: 05 May 2011
Posts: 32
Own Kudos:
44
Given Kudos: 5
Posts: 32
Kudos: 44
If x and y are positive integers, is x an even int? 1) 29 Oct 2007, 12:46
Kudos
Add Kudos
Bookmarks
Bookmark this Post
C

Start with stmt 2:

Plug in 1 in (2) and it yields 6+41+25 = 72 which is even
Plug in 2 in (2) and it yields 24+82+25 = 131 which is odd
Plug in 3 in (2) and it yields 54+123+25 = 202 which is even
Plug in 4 in (2) and it yields 96+164+25 = 285 which is odd

It tells us that y is odd but doesn't tell anything about x

Now come to stmt1
Plug in 1 for y in (1) and it yeilds = 6x which is even for any values of x
Plug in 3 for y in (1) and it yeilds = 8x which is even for any values of x

So, both statements are required.
User avatar
sevenplus
User avatar
Joined: 26 Sep 2007
Last visit: 05 May 2011
Posts: 32
Own Kudos:
44
Given Kudos: 5
Posts: 32
Kudos: 44
If x and y are positive integers, is x an even int? 1) 29 Oct 2007, 16:00
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Careless mistake. Even after solving the whole thing picked wrong one. Yes, x can be either even or odd as per these two statements. So no definitve answer. E
User avatar
GMATBLACKBELT
User avatar
Joined: 29 Mar 2007
Last visit: 03 Jun 2013
Posts: 1,138
Own Kudos:
1,916
Posts: 1,138
Kudos: 1,916
If x and y are positive integers, is x an even int? 1) 29 Oct 2007, 21:55
Kudos
Add Kudos
Bookmarks
Bookmark this Post
combres
If x and y are positive integers, is x an even int?

1) x(y+5) is an even int
2) 6y^2 + 41y + 25 is even int


I can't seem to find a way for (2) to be an even integer no matter what I plug in and I think it is a waste of time to factor (2)

any ideas?
Show more


1) x can be ever or odd. Try x = 2 ,y=3 and x=3 y=3

Insuff.

2) nothing about X. but it does establish that y must be odd. here is why:
6y^2+41y+25

O=odd
E=Even

6(O)+41(O) +25 ---> E+O +O --> O +O--> Even

If y is even then 6(E) +41(E) +25---> E+E+O which is NOT even.

1&2:

X can still be even or odd. If y is odd then y+5 must be even. however, if x is odd O(E)=E or E(E)=E.

Insuff.


E
User avatar
ywilfred
User avatar
Joined: 07 Jul 2004
Last visit: 06 Mar 2012
Posts: 1,987
Own Kudos:
2,053
Location: Singapore
Posts: 1,987
Kudos: 2,053
If x and y are positive integers, is x an even int? 1) 30 Oct 2007, 03:32
Kudos
Add Kudos
Bookmarks
Bookmark this Post
St1:
x(y+5) could be x = even or (y+5) = even or both even. Insufficient.

St2:
6y^2 + 41y + 25 = even

25 = odd

Can be 6y^2 = odd, 41y = even, 25 =odd then odd+even+odd = even.
But if 41y = even, then y must be even and y^2 = even and 6y^2 cannot be odd.

So it must be 6y^2 = even, 41y = odd, 25 = odd then even+odd+odd= even.
Now we know y = odd. But we do not know x. Insufficient.

St1 and St2:
Since we know y is odd, y+5 = even. So x(y+5) = even but x can be odd or even. Insufficient.

Ans E



Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block above for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!