Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 25 Oct 2016, 14:43

### 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 a and b are integers, and |a| > |b|, is a |b| < a

Author Message
TAGS:

### Hide Tags

Senior Manager
Joined: 12 May 2010
Posts: 288
Location: United Kingdom
Concentration: Entrepreneurship, Technology
GMAT Date: 10-22-2011
GPA: 3
WE: Information Technology (Internet and New Media)
Followers: 4

Kudos [?]: 57 [0], given: 12

If a and b are integers, and |a| > |b|, is a |b| < a [#permalink]

### Show Tags

17 Mar 2011, 10:49
00:00

Difficulty:

85% (hard)

Question Stats:

38% (01:58) correct 62% (02:28) wrong based on 13 sessions

### HideShow timer Statistics

If a and b are integers, and |a| > |b|, is a · |b| < a – b?

(1) a < 0

(2) ab >= 0
[Reveal] Spoiler: OA

Last edited by n2739178 on 18 Mar 2011, 04:20, edited 1 time in total.
Manager
Joined: 03 Mar 2011
Posts: 90
Location: United States
Schools: Erasmus (S)
GMAT 1: 730 Q51 V37
GPA: 3.9
Followers: 2

Kudos [?]: 131 [0], given: 12

Re: How to solve quickly!?!? [#permalink]

### Show Tags

17 Mar 2011, 13:28

Regarding (1):
It is obviously not enough.
Assume that b is 0 and a is -1. Then the inequality is 0<-1 which is false
Assume that b is -1 and a is -2. Then the inequality is -2<-1 which is true
_________________

If my post is useful for you not be ashamed to KUDO me!
Let kudo each other!

Intern
Joined: 17 Mar 2011
Posts: 17
Followers: 0

Kudos [?]: 11 [0], given: 0

Re: How to solve quickly!?!? [#permalink]

### Show Tags

17 Mar 2011, 19:00
You dont need to know the sign dood. You have the official answer, which is E.

Therefore the sign must have been ab <0.

(If it was ab>0 then we would know that both a and b are positive integers. This would be enough information to know that the above inequality is always incorrect).

Therefore we know that a is +ve integer, b is -ve integer. Unfortunately this information does not let us solve it, and to solve this quickly we just plug in numbers.

A=5, B=-2.... 10>7
A=5, B=-1.....5<6. We dont know from both so E, quickly move on.
SVP
Joined: 16 Nov 2010
Posts: 1673
Location: United States (IN)
Concentration: Strategy, Technology
Followers: 34

Kudos [?]: 491 [0], given: 36

Re: How to solve quickly!?!? [#permalink]

### Show Tags

17 Mar 2011, 22:39
From 1, a < 0

Now a is -ve, and b can be -ve or +ve

if a = -2, -1 <= b <= 1

-2 *|-1| < -2 -(-1)

-2 < -1

But -2.|1| > -2 - (1) because -2 > -3, so (1) is insufficient

If ab < 0 then they have opposite signs, hence the same problem as above:

Combining (1) and (2), not sufficient, b > 0, but :

if a = -1, b = 6

a * |b| = -6 > -7

if a = -1 b = 1

a*|b| = -1 > -2

@bostonrb, I think you might want to take -ve values of A and prove it ?
_________________

Formula of Life -> Achievement/Potential = k * Happiness (where k is a constant)

GMAT Club Premium Membership - big benefits and savings

SVP
Joined: 16 Nov 2010
Posts: 1673
Location: United States (IN)
Concentration: Strategy, Technology
Followers: 34

Kudos [?]: 491 [0], given: 36

Re: How to solve quickly!?!? [#permalink]

### Show Tags

17 Mar 2011, 22:43
Btw, I searched for this and in MGMAT forum it is suggested that the symbol is ab >= 0 and the answer is still E.

http://www.manhattangmat.com/forums/if- ... t9437.html
_________________

Formula of Life -> Achievement/Potential = k * Happiness (where k is a constant)

GMAT Club Premium Membership - big benefits and savings

Intern
Joined: 17 Mar 2011
Posts: 17
Followers: 0

Kudos [?]: 11 [0], given: 0

Re: How to solve quickly!?!? [#permalink]

### Show Tags

17 Mar 2011, 23:06
Yeah subhash, I misread (1) as saying that a is +ve, hence everything I wrote is for that case.. (why I always get a couple questions wrong in Q =/)

If we take ab>=0 as per the link, and a<0, then a is -ve, b is 0 or -ve.

choose a=-5. is -5 |b|<-5-b ??? For any neg integer b, RHS will at least be -4 while LHS will at most be -5. Therefore it would be (C).. only b can be 0! In that case it doesnt stand, 0 is not <a (as per statement 1), so the possibility of b=0 makes it (E).

Last edited by bostonrb on 18 Mar 2011, 05:06, edited 1 time in total.
Senior Manager
Joined: 12 May 2010
Posts: 288
Location: United Kingdom
Concentration: Entrepreneurship, Technology
GMAT Date: 10-22-2011
GPA: 3
WE: Information Technology (Internet and New Media)
Followers: 4

Kudos [?]: 57 [0], given: 12

Re: How to solve quickly!?!? [#permalink]

### Show Tags

18 Mar 2011, 04:20
forgot to put the operator in statement 2... amended. apologies!

(2) ab >= 0
Re: How to solve quickly!?!?   [#permalink] 18 Mar 2011, 04:20
Similar topics Replies Last post
Similar
Topics:
3 If a and b are integers, and |a| > |b|, is a |b| < a 7 27 Apr 2011, 22:58
1 If a and b are integers, and |a| > |b|, is a |b| < a 6 19 Sep 2010, 13:21
10 If a and b are integers, and |a| > |b|, is a |b| < a 19 10 Oct 2009, 06:51
33 If a and b are integers, and |a| > |b|, is a |b| < a 26 11 Sep 2009, 01:57
9 If a and b are integers, and |a| > |b|, is a |b| < a 14 26 Dec 2006, 19:36
Display posts from previous: Sort by