Find all School-related info fast with the new School-Specific MBA Forum
Learn more about the recent changes... close

It is currently 20 May 2013, 01:14
Customize  |  Hide

Search
Register
New posts
Unanswered

If r + s > 2t, is r > t ? (1) t > s (2) r > s

  Question banks Downloads My Bookmarks Reviews  
  Oldest Best Reply
Search for:
 
Print view
First unread post
Author Message
TAGS:
1 KUDOS received
Manager
Manager
Joined: 11 Aug 2009
Posts: 132
Followers: 1

Kudos [?]: 10 [1] , given: 3

GMAT Tests User
If r + s > 2t, is r > t ? (1) t > s (2) r > s [#permalink] New post 19 Nov 2009, 06:54
1
This post received
KUDOS
00:00

Question Stats:

36% (02:07) correct 63% (00:53) wrong based on 4 sessions
If r + s > 2t, is r > t ?

(1) t > s

(2) r > s
[Reveal] Spoiler: OA

Last edited by Bunuel on 26 Mar 2012, 00:36, edited 1 time in total.
Edited the question and added the OA
VP
VP
Joined: 05 Mar 2008
Posts: 1489
Followers: 10

Kudos [?]: 164 [0], given: 31

GMAT Tests User
Re: If r + s > 2t, is r > t ? [#permalink] New post 19 Nov 2009, 08:33
kairoshan wrote:
If r + s > 2t, is r > t ?

(1) t > s

(2) r > s


answer D

1.
r + s > 2t
s<t

subtract inequalities and you get r>t so sufficient

2. r>s or r-s>0
r+s>2t

add equations and you get 2r>2t or r>t
Manager
Manager
User avatar
Joined: 27 Oct 2011
Posts: 196
Location: United States
Concentration: Finance, Strategy
Schools: HBS '15 (D), Stanford '15 (S), Haas '15 (S), Anderson '15 (S), Marshall '15
GMAT 1: Q V
GPA: 3.7
WE: Account Management (Consumer Products)
Followers: 1

Kudos [?]: 25 [0], given: 4

Re: If r + s > 2t, is r > t ? (1) t > s (2) r > s [#permalink] New post 25 Mar 2012, 17:44
thx lagomez. just forgot that we could add inequalities and equations to help simplify an equation.
_________________

DETERMINED TO BREAK 700!!!

6 KUDOS received
GMAT Club team member
User avatar
Joined: 02 Sep 2009
Posts: 11518
Followers: 1792

Kudos [?]: 9538 [6] , given: 826

GMAT Tests User CAT Tests
Top Member of the Month
Re: If r + s > 2t, is r > t ? (1) t > s (2) r > s [#permalink] New post 26 Mar 2012, 00:40
6
This post received
KUDOS
If r + s > 2t, is r > t ?

(1) t > s --> since the signs of two equations (t > s and r + s > 2t) are the same direction we can sum them: t+(r+s)>s+2t --> r>t. Sufficient.

(2) r > s --> the same here: since the signs of two equations (r > s and r + s > 2t) are the same direction we can sum them: r+(r+s)>s+2t --> 2r>2t --> r>t. Sufficient.

Answer: D.

THEORY:
You can only add inequalities when their signs are in the same direction:

If a>b and c>d (signs in same direction: > and >) --> a+c>b+d.
Example: 3<4 and 2<5 --> 3+2<4+5.

You can only apply subtraction when their signs are in the opposite directions:

If a>b and c<d (signs in opposite direction: > and <) --> a-c>b-d (take the sign of the inequality you subtract from).
Example: 3<4 and 5>1 --> 3-5<4-1.

Hope it helps.
_________________

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. NEW!!!

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set. NEW!!!


What are GMAT Club Tests?
25 extra-hard Quant Tests

Find out what's new at GMAT Club - latest features and updates

Intern
Intern
Joined: 20 Feb 2013
Posts: 5
Followers: 0

Kudos [?]: 5 [0], given: 0

Re: If r + s > 2t, is r > t ? (1) t > s (2) r > s [#permalink] New post 20 Mar 2013, 23:13
Hi Bunnel, since we don't know the signs of t and s, how can we subtract s on both sides to simplify the inequality R+s+t>S+2T? Am I missing something here?

Bunuel wrote:
If r + s > 2t, is r > t ?

(1) t > s --> since the signs of two equations (t > s and r + s > 2t) are the same direction we can sum them: t+(r+s)>s+2t --> r>t. Sufficient.

(2) r > s --> the same here: since the signs of two equations (r > s and r + s > 2t) are the same direction we can sum them: r+(r+s)>s+2t --> 2r>2t --> r>t. Sufficient.

Answer: D.

THEORY:
You can only add inequalities when their signs are in the same direction:

If a>b and c>d (signs in same direction: > and >) --> a+c>b+d.
Example: 3<4 and 2<5 --> 3+2<4+5.

You can only apply subtraction when their signs are in the opposite directions:

If a>b and c<d (signs in opposite direction: > and <) --> a-c>b-d (take the sign of the inequality you subtract from).
Example: 3<4 and 5>1 --> 3-5<4-1.

Hope it helps.
GMAT Club team member
User avatar
Joined: 02 Sep 2009
Posts: 11518
Followers: 1792

Kudos [?]: 9538 [0], given: 826

GMAT Tests User CAT Tests
Top Member of the Month
Re: If r + s > 2t, is r > t ? (1) t > s (2) r > s [#permalink] New post 21 Mar 2013, 03:33
AnnT wrote:
Hi Bunnel, since we don't know the signs of t and s, how can we subtract s on both sides to simplify the inequality R+s+t>S+2T? Am I missing something here?

Bunuel wrote:
If r + s > 2t, is r > t ?

(1) t > s --> since the signs of two equations (t > s and r + s > 2t) are the same direction we can sum them: t+(r+s)>s+2t --> r>t. Sufficient.

(2) r > s --> the same here: since the signs of two equations (r > s and r + s > 2t) are the same direction we can sum them: r+(r+s)>s+2t --> 2r>2t --> r>t. Sufficient.

Answer: D.

THEORY:
You can only add inequalities when their signs are in the same direction:

If a>b and c>d (signs in same direction: > and >) --> a+c>b+d.
Example: 3<4 and 2<5 --> 3+2<4+5.

You can only apply subtraction when their signs are in the opposite directions:

If a>b and c<d (signs in opposite direction: > and <) --> a-c>b-d (take the sign of the inequality you subtract from).
Example: 3<4 and 5>1 --> 3-5<4-1.

Hope it helps.


You are mixing subtraction/addition with multiplication/division. We are only concerned with sign when we multiply/divide an inequality.
_________________

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. NEW!!!

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set. NEW!!!


What are GMAT Club Tests?
25 extra-hard Quant Tests

Find out what's new at GMAT Club - latest features and updates

Re: If r + s > 2t, is r > t ? (1) t > s (2) r > s   [#permalink] 21 Mar 2013, 03:33
    Similar topics Author Replies Last post
Similar
Topics:
 New posts If r + s > 2t, is r > t ? (1) t > s (2) r > s dreamgmat1 2 09 Jul 2007, 20:05
New posts 2 If r + s > 2t, is r > t ? (1) t > s (2) r > s mrwaxy 4 31 May 2008, 09:49
New posts If r + s > 2t, is r > t ? (1) t > s (2) r > s study 9 12 Dec 2008, 05:12
New posts 1 If r + s > 2t, is r > t ? (1) t > s (2) r > s Is gmatprep09 2 20 May 2009, 15:43
New posts 1 If r + s > 2t, is r > t ? (1) t > s (2) r > s Wayxi 2 04 Jan 2011, 22:07
Display posts from previous: Sort by

If r + s > 2t, is r > t ? (1) t > s (2) r > s

  Question banks Downloads My Bookmarks Reviews  
Print view
First unread post

Moderators: Bunuel, VeritasPrepKarishma, IanStewart

Search for:


GMAT Club MBA Forum Home| About| Privacy Policy| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

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®.

Main navigation

GMAT Resources

Partners

MBA Resources

www.gmac.com|www.mba.com