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

It is currently 22 Feb 2019, 16:46

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
Events & Promotions in February
PrevNext
SuMoTuWeThFrSa
272829303112
3456789
10111213141516
17181920212223
242526272812
Open Detailed Calendar
  • Free GMAT RC Webinar

     February 23, 2019

     February 23, 2019

     07:00 AM PST

     09:00 AM PST

    Learn reading strategies that can help even non-voracious reader to master GMAT RC. Saturday, February 23rd at 7 AM PT
  • FREE Quant Workshop by e-GMAT!

     February 24, 2019

     February 24, 2019

     07:00 AM PST

     09:00 AM PST

    Get personalized insights on how to achieve your Target Quant Score.

Is m/n < mn? (1) mn is positive (2) n < -1

  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: 53066
Is m/n < mn? (1) mn is positive (2) n < -1  [#permalink]

Show Tags

New post 09 Oct 2018, 02:17
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

50% (01:42) correct 50% (02:08) wrong based on 32 sessions

HideShow timer Statistics

Manager
Manager
avatar
B
Joined: 22 Jan 2018
Posts: 54
Location: India
Concentration: Operations, Technology
GMAT 1: 650 Q44 V35
GPA: 4
GMAT ToolKit User Reviews Badge CAT Tests
Is m/n < mn? (1) mn is positive (2) n < -1  [#permalink]

Show Tags

New post Updated on: 09 Oct 2018, 03:23
Bunuel wrote:
Is m/n < mn?

(1) mn is positive
(2) n < -1


Both values of m & n are either positive or negative.

1- m*n>0 ( it shows moth are either positive or negative )
no other information can be taken out from this.
:. not sufficient

2- n<-1 ( it says n is negative, so m will also be negative)
No other information can be taken out from this.
:. not sufficient

1-2 combined - as n<-1 (n can be = -2,-3,....) and m is also negative,
m/n < m*n always.

:.the correct answer should be, C.

Give Kudos, if it helped. :)

Originally posted by shiva007 on 09 Oct 2018, 02:42.
Last edited by shiva007 on 09 Oct 2018, 03:23, edited 1 time in total.
CEO
CEO
User avatar
P
Status: GMATINSIGHT Tutor
Joined: 08 Jul 2010
Posts: 2799
Location: India
GMAT: INSIGHT
Schools: Darden '21
WE: Education (Education)
Reviews Badge
Re: Is m/n < mn? (1) mn is positive (2) n < -1  [#permalink]

Show Tags

New post 09 Oct 2018, 03:07
Bunuel wrote:
Is m/n < mn?

(1) mn is positive
(2) n < -1


Question: Is m/n < mn?

In this question we can't further simplify because we do NOT know signs of m and n therefore we straight go to statements to see how useful they may be to determine the answer

Statement 1: mn is positive
i.e. Either both m and n are positive OR both are Negative
Case 1: m = 3 and n = 2, m/n < mn
Case 2: m = 3 and n = 1/2, m/n is NOT less than mn hence
NOT SUFFICIENT

Statement 2: n < -1
No information about m hence
NOT SUFFICIENT

Combining the two statements
Statement 2 says n < -1 i.e. m also is Negative
i.e. Question asked Is m/n < mn may be written as
Is 1/n > n?
But if n < -1 then 1/n is ALWAYS greater than n hence
SUFFICIENT

Answer: Option C
_________________

Prosper!!!
GMATinsight
Bhoopendra Singh and Dr.Sushma Jha
e-mail: info@GMATinsight.com I Call us : +91-9999687183 / 9891333772
Online One-on-One Skype based classes and Classroom Coaching in South and West Delhi
http://www.GMATinsight.com/testimonials.html

ACCESS FREE GMAT TESTS HERE:22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION

Intern
Intern
User avatar
B
Joined: 24 Jun 2018
Posts: 31
Re: Is m/n < mn? (1) mn is positive (2) n < -1  [#permalink]

Show Tags

New post 09 Oct 2018, 03:08
Bunuel wrote:
Is m/n < mn?

(1) mn is positive
(2) n < -1


Statement 1: insufficient. mn is positive - suggests that the value of both m and n are same, however, the value can vary and thus the statement will not be sufficient.
Statement 2: insufficient: if n is less than -1 than the value of m can be positive and negative. giving us two sets of answers.

Both statement together is sufficient. from info in statement 2 we can rewrite the question as - is m>mn^2, thus we only need to establish that m is negative. statement 1 tells us that mn is positive thus m is negative, hence sufficient.
_________________

A sentence which can make a happy person sad and a sad person happy- 'this TIME will change'

Manager
Manager
User avatar
S
Joined: 08 Sep 2008
Posts: 123
Location: India
Concentration: Operations, General Management
Schools: ISB '20
GPA: 3.8
WE: Operations (Transportation)
CAT Tests
Re: Is m/n < mn? (1) mn is positive (2) n < -1  [#permalink]

Show Tags

New post 09 Oct 2018, 03:13
Bunuel wrote:
Is m/n < mn?

(1) mn is positive
(2) n < -1


Statement 1:
mn positive means both m and n has same sign.
Let’s take m and n positive

M=2, N=2
Value of m/n<mn ( 2/2<2*2) answer yes

M=0.5 , N=0.5
Value of equation ( 0.5/0.5not < 0.5*0.5) answer no

Statement 1 not sufficient

Statement 2:
N negative, but no information about m
M can be zero then answer is no n can be other values answer will be yes.
Not sufficient.

Combine:
We conclude both m and n is negative with n being less than -1.
Now when we divide or multiply two negative it will give result in positive.
And N being less than -1 it will give a yes answer.
E.g.
M=-0.5, N=-1.1
Equation
0.5/1.1< 0.55


So sufficient
Answer C(IMO)


Sent from my iPad using GMAT Club Forum mobile app
_________________

Regards;
Vishal

+==========+
Kudos if it deserve....one...

Director
Director
avatar
G
Joined: 19 Oct 2013
Posts: 508
Location: Kuwait
GPA: 3.2
WE: Engineering (Real Estate)
GMAT ToolKit User
Is m/n < mn? (1) mn is positive (2) n < -1  [#permalink]

Show Tags

New post 09 Oct 2018, 05:07
Bunuel wrote:
Is m/n < mn?

(1) mn is positive
(2) n < -1


let m = 2 and n = 3

\(\frac{2}{3}\)< 6? yes

let m = 3 and n = \(\frac{1}{3}\)

\(\frac{3}{(1/3)}\) = \(3 * 3 = 9\)

9 < 3 * \(\frac{1}{3}\) no

Two different answers.

1 is insufficient.

2)

we are given n <-1

let m = 2 and n = -2

\(\frac{2}{-2}\)= -1

-1 < -4 no

let m = -9 and n = -3

\(\frac{-9}{-3}\)= 3

3 < 27 yes.

again two different answers not sufficient.

combine (1) and (2)

we know n is negative and mn is positive.

so m has to be negative.

let n = -2 and m = -2

\(\frac{-2}{-2}\) = 1

1 < 4

since n is not between 0 and -1 the left side will never be larger. we get a sufficient answer

\(\frac{m}{n}\) will be > mn only if n lies between 0 and 1 or 0 and -1
GMAT Club Bot
Is m/n < mn? (1) mn is positive (2) n < -1   [#permalink] 09 Oct 2018, 05:07
Display posts from previous: Sort by

Is m/n < mn? (1) mn is positive (2) n < -1

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


Copyright

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®.