It is currently 29 Jun 2017, 09:13

### 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

# Events & Promotions

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

# If a and b are integers, is b even? (1) 3a + 4b is even (2)

 post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
Director
Joined: 05 Jan 2008
Posts: 688
If a and b are integers, is b even? (1) 3a + 4b is even (2) [#permalink]

### Show Tags

10 May 2008, 03:23
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 1 sessions

### HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

If a and b are integers, is b even?

(1) 3a + 4b is even
(2) 3a + 5b is even

(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
(D) EACH statement ALONE is sufficient.
(E) Statements (1) and (2) TOGETHER are NOT sufficient.
_________________

Persistence+Patience+Persistence+Patience=G...O...A...L

Director
Joined: 14 Oct 2007
Posts: 753
Location: Oxford
Schools: Oxford'10
Re: DS: Even [#permalink]

### Show Tags

10 May 2008, 06:13
from 1) we know that either 3a and 4b are both even or both odd, however 4b can never be odd. This leaves us with 4b = even, but b can be either even or odd. so insuff

from 2) we know that either 3a and 5b are both even or both odd. If 5b is even, b is even. If 5b is odd, b is odd. insuff

from 1)2) we know that 3a being odd is never a possibility, so 4b and 5b BOTH are even, hence b = even

ans = C
Manager
Joined: 31 Oct 2007
Posts: 113
Location: Frankfurt, Germany
Re: DS: Even [#permalink]

### Show Tags

10 May 2008, 07:15
prasannar wrote:
If a and b are integers, is b even?

(1) 3a + 4b is even
(2) 3a + 5b is even

(A) Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient.
(B) Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient.
(C) BOTH statements TOGETHER are sufficient, but NEITHER statement ALONE is sufficient.
(D) EACH statement ALONE is sufficient.
(E) Statements (1) and (2) TOGETHER are NOT sufficient.

Is b even?

Statement (1) alone 3a + 4b = even. Since any number multiply by an even number, in this case 4, must be even. b can be odd or even. 3a cannot be odd since only even + even = even. Not sufficient. Eliminate A and D.

Statement (2) alone 3a +5b = even. Again, any number multiply by an odd number will be can be odd or even. Thus, a and b can be odd or even numbers.

However, only odd + odd = even or even + even = even (even + odd = odd). Since 5b can be odd or even. Not sufficient. Eliminate B.

Statement (1) and (2) together. From statement (1), b can be odd or even. From statement (2), b can also be odd or even. Thus, we can't be certain if b is odd or even. Eliminate C.

Ans: E
_________________

Jimmy Low, Frankfurt, Germany
Blog: http://mytrainmaster.wordpress.com
GMAT Malaysia: http://gmatmalaysia.blogspot.com

Director
Joined: 14 Oct 2007
Posts: 753
Location: Oxford
Schools: Oxford'10
Re: DS: Even [#permalink]

### Show Tags

10 May 2008, 07:29
Quote:
Statement (1) and (2) together. From statement (1), b can be odd or even. From statement (2), b can also be odd or even. Thus, we can't be certain if b is odd or even. Eliminate C.

yes but you have to dig a bit deeper. from statement 1) we can see that 3a has to be even, since 4b will ALWAYS be even. given that fact, 3a in statement 2) has to be even too. and if 3a in statement 2) is even, 5b in statement 2) has to be even, hence b has to be even..

C) for me
Re: DS: Even   [#permalink] 10 May 2008, 07:29
Display posts from previous: Sort by

# If a and b are integers, is b even? (1) 3a + 4b is even (2)

 post reply Question banks Downloads My Bookmarks Reviews Important topics

 Powered by phpBB © phpBB Group and phpBB SEO 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®.