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

 It is currently 06 Jul 2015, 04:19

### 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

# Is 1/ ( a-b ) < b-a? 1. a<b 2.1<|a-b

Author Message
TAGS:
Manager
Joined: 20 Nov 2004
Posts: 108
Followers: 0

Kudos [?]: 2 [0], given: 0

chiragr wrote:
so a-b is negative and b-a is positive
=> 1/a-b is negative and b-a is positive

H E L P

Am I the only one who thinks that it's a major difference if it's
1/a-b OR
1/(a-b)

I'm sorry, but the question tells us that it's
1/a-b = (1/a) - b
AND NOT
1 / (a-b)
.

The problem is, that this - besides the math - leads to another answer,
which is E.
SVP
Joined: 03 Jan 2005
Posts: 2246
Followers: 13

Kudos [?]: 226 [0], given: 0

Here's my solution. I only have 1 minute so please let me know if the logic is not correct.

We want to know if 1/(a-b)<b-a

In other words if (b-a)-1/(a-b)>0
or if (-(a-b)^2-1)/(a-b)>0

We can see that the numerator is definitely negative. So the only thing we need to know is if a-b>0

2) a-b could be negative or positive. Thus insufficent.

_________________

Keep on asking, and it will be given you;
keep on seeking, and you will find;
keep on knocking, and it will be opened to you.

Manager
Joined: 20 Nov 2004
Posts: 108
Followers: 0

Kudos [?]: 2 [0], given: 0

HongHu wrote:
I only have 1 minute so please let me know if the logic is not correct.

Well done for a minute and the logic IS correct
Manager
Joined: 08 Feb 2006
Posts: 128
Followers: 1

Kudos [?]: 7 [0], given: 0

I got A.

Statement 2 is not sufficient.

I tried a=4, b=1 which did not satisfy both equations.
Next, I tried a=-2, b=2, which satisfied both equations.

Go to page   Previous    1   2   [ 24 posts ]

Similar topics Replies Last post
Similar
Topics:
Is (A/B)^3<(AB)^3 1) A>0 2) AB>0 6 05 Sep 2011, 01:18
Is 1/(a-b) < b-a ? 3 01 Jan 2007, 17:24
25 Is 1/(a-b) < b-a ? (1) a<b (2) 1<|a-b 18 30 Jun 2006, 05:49
Is 1/(a-b) < b-a? (1) a < b (2) 1 < |a-b 8 27 Oct 2005, 15:27
Display posts from previous: Sort by

# Is 1/ ( a-b ) < b-a? 1. a<b 2.1<|a-b

 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®.