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

 It is currently 27 Oct 2016, 16:29

### 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

# There was a prob with my calc the first time around. I've

Author Message
Director
Joined: 12 Jun 2006
Posts: 532
Followers: 2

Kudos [?]: 110 [0], given: 1

There was a prob with my calc the first time around. I've [#permalink]

### Show Tags

02 Mar 2007, 00:14
00:00

Difficulty:

(N/A)

Question Stats:

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

### HideShow timer Statistics

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

There was a prob with my calc the first time around. I've since corrected this prob.

if m>0 and n>0 is m+x/n+x > m/n?

stmnt 1: m is greater than n
stmnt 2: x is greater than 0

m+x/n+x > m/n =

m+x/n+x - m/n > 0 =

n(m+x)/n(n+x) - m(n+x)/n(n+x) > 0 = nm + nx - mn - mx/n^2 + nx =

nx - mx/n^2 + nx = -mx/n^2

Rephrased, the question reads: is -mx/n^2 > 0?

I picked b. The stem states that m and n are greater than 0. Statement 2 says that x is greater than 0. If m, n and x are all greater than 0 the equation must be greater than 0 too. The answer is C. Where did I go wrong?

Last edited by ggarr on 02 Mar 2007, 04:40, edited 5 times in total.
Manager
Joined: 12 May 2006
Posts: 185
Followers: 1

Kudos [?]: 54 [0], given: 0

### Show Tags

02 Mar 2007, 03:27
I guess there is a small problem in the calculation below. Following is my explaination:

m+x/n+x > m/n =

m+x/n+x - m/n > 0 =

[n(m+x) - m(n+x)]/n(n+x) > 0

[n(m+x) - m(n+x)] > 0

mn + nx - mn - mx > 0

x(n-m) > 0

=> x > 0 & n>m OR x< 0 & n<m

However both of these does not match with the given statements hence the answer should be E.
Senior Manager
Joined: 29 Jan 2007
Posts: 450
Location: Earth
Followers: 2

Kudos [?]: 61 [0], given: 0

### Show Tags

02 Mar 2007, 11:38
I agree answer has to be C.

I did it this way.

We know that a/b = c/d
then

(a-b)/b = (c-d)/d

If you apply that
Question becomes
Is (m+x-n-x)/(n+x) > (m-n)/n

so

Is (m-n)/(n+x) > (m-n)/n

Stmt 1
m > n ...so numerators are positive...but X is not known to be -ve or +ve...

so NOT SUFF

Stmt 2
x >0..so Denominator on left is greater than that on right...
but Is m-n negative or positive? Not known so we can NOT tell if left > right ( example here is 2 < 5 but -2 > -5... so we need to know the sign)

so NOT SUFF.

If you combine 1 and 2...its SUFF so answer C.
Senior Manager
Joined: 29 Jan 2007
Posts: 450
Location: Earth
Followers: 2

Kudos [?]: 61 [0], given: 0

### Show Tags

02 Mar 2007, 11:59
grepro

you simplified it to

Is x(n-m) > 0 ?

You can answer this question when you know
Sign of X and Sign of (n-m)

Stmt 1 and 2 combined give you that information. So answer is C.
Display posts from previous: Sort by