GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 20 Sep 2018, 13:31

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

If |a| + |b| = |a + b|, a ≠ 0, and b ≠ 0, then which of the following

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

Hide Tags

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 49271
If |a| + |b| = |a + b|, a ≠ 0, and b ≠ 0, then which of the following  [#permalink]

Show Tags

New post 03 Jul 2018, 09:49
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

84% (00:54) correct 16% (01:17) wrong based on 118 sessions

HideShow timer Statistics

BSchool Forum Moderator
User avatar
D
Joined: 28 Mar 2017
Posts: 1130
Location: India
GMAT 1: 730 Q49 V41
GPA: 4
CAT Tests
Re: If |a| + |b| = |a + b|, a ≠ 0, and b ≠ 0, then which of the following  [#permalink]

Show Tags

New post 03 Jul 2018, 09:56
1
oskarw93s wrote:
B

Posted from my mobile device


Hi, just stating the answer won't help anyone including yourself. Try to elaborate on the approach you used to solve the question; that way, if you would have had any wrong in your strategy then someone might be able to point that out, helping the community !
_________________

Kudos if my post helps!

Long And A Fruitful Journey - V21 to V41; If I can, So Can You!!


Preparing for RC my way


My study resources:
1. Useful Formulae, Concepts and Tricks-Quant
2. e-GMAT's ALL SC Compilation
3. LSAT RC compilation
4. Actual LSAT CR collection by Broal
5. QOTD RC (Carcass)
6. Challange OG RC
7. GMAT Prep Challenge RC

Intern
Intern
avatar
B
Joined: 05 May 2018
Posts: 7
Re: If |a| + |b| = |a + b|, a ≠ 0, and b ≠ 0, then which of the following  [#permalink]

Show Tags

New post 03 Jul 2018, 10:37
1
Bunuel wrote:
If |a| + |b| = |a + b|, a ≠ 0, and b ≠ 0, then which of the following must be true?


A. ab < 0

B. ab > 0

C. a - b > 0

D. a + b < 0

E. a + b > 0
For this equation to be true .. a and b both should either positive or negative .. Which is ab>0 .. Hence B.

Sent from my A0001 using GMAT Club Forum mobile app
Director
Director
User avatar
G
Joined: 31 Oct 2013
Posts: 574
Concentration: Accounting, Finance
GPA: 3.68
WE: Analyst (Accounting)
Re: If |a| + |b| = |a + b|, a ≠ 0, and b ≠ 0, then which of the following  [#permalink]

Show Tags

New post 17 Jul 2018, 17:09
Bunuel wrote:
If |a| + |b| = |a + b|, a ≠ 0, and b ≠ 0, then which of the following must be true?


A. ab < 0

B. ab > 0

C. a - b > 0

D. a + b < 0

E. a + b > 0



Given

|a| + |b| = |a + b|

Let assume the value of a and b

a = -2 or 2

b = -2 or 2

Both cases given equation is true. Either both of the a and b are positive or both of them are negative. Other combinations are not working here.

Thus ab>0 is true.

The best answer is B.
Math Expert
User avatar
V
Joined: 02 Aug 2009
Posts: 6797
Re: If |a| + |b| = |a + b|, a ≠ 0, and b ≠ 0, then which of the following  [#permalink]

Show Tags

New post 17 Jul 2018, 21:53
1
Bunuel wrote:
If |a| + |b| = |a + b|, a ≠ 0, and b ≠ 0, then which of the following must be true?


A. ab < 0

B. ab > 0

C. a - b > 0

D. a + b < 0

E. a + b > 0


|When is this possible, ONLY when both a and b are on same side of 0 or in other words both have same sign...
Please see attached figure..

If a and b are of same sign a*b>0

B
Attachments

PicsArt_07-18-10.22.49.jpg
PicsArt_07-18-10.22.49.jpg [ 51.16 KiB | Viewed 536 times ]


_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html


GMAT online Tutor

Re: If |a| + |b| = |a + b|, a ≠ 0, and b ≠ 0, then which of the following &nbs [#permalink] 17 Jul 2018, 21:53
Display posts from previous: Sort by

If |a| + |b| = |a + b|, a ≠ 0, and b ≠ 0, then which of the following

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

Events & Promotions

PREV
NEXT


GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| 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®.