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

 It is currently 17 Dec 2018, 06:38

# R1 Decisions:

Michigan Ross Chat (US calls are expected today)  |  UCLA Anderson Chat  (Calls expected to start at 7am PST; Applicants from Asia will hear first)

### 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 December
PrevNext
SuMoTuWeThFrSa
2526272829301
2345678
9101112131415
16171819202122
23242526272829
303112345
Open Detailed Calendar
• ### 10 Keys to nail DS and CR questions

December 17, 2018

December 17, 2018

06:00 PM PST

07:00 PM PST

Join our live webinar and learn how to approach Data Sufficiency and Critical Reasoning problems, how to identify the best way to solve each question and what most people do wrong.
• ### R1 Admission Decisions: Estimated Decision Timelines and Chat Links for Major BSchools

December 17, 2018

December 17, 2018

10:00 PM PST

11:00 PM PST

From Dec 5th onward, American programs will start releasing R1 decisions. Chat Rooms: We have also assigned chat rooms for every school so that applicants can stay in touch and exchange information/update during decision period.

# If x + y + z > 0, is z > 1?

Author Message
TAGS:

### Hide Tags

Intern
Joined: 24 May 2009
Posts: 33
If x + y + z > 0, is z > 1?  [#permalink]

### Show Tags

14 Nov 2009, 01:41
1
17
00:00

Difficulty:

55% (hard)

Question Stats:

63% (01:49) correct 37% (02:11) wrong based on 344 sessions

### HideShow timer Statistics

If x + y + z > 0, is z > 1?

(1) z > x + y +1
(2) x + y + 1 < 0
Math Expert
Joined: 02 Sep 2009
Posts: 51261
Re: DS- inequalities is Z>1?  [#permalink]

### Show Tags

14 Nov 2009, 01:52
3
7
RisingForceX wrote:
If x+y+z > 0, is z > 1?

(1) z > x + y +1
(2) x + y + 1 < 0

Remember we can add inequalities when their signs are in the same direction and subtract inequalities when their signs are in the opposite direction.

(1) z > x + y +1 and x+y+z > 0 --> adding inequalities x+y+z+z>x + y +1 --> z>1/2. Not sufficient.

(2) x + y + 1 < 0 and x+y+z > 0 --> subtract inequalities z-1>0 --> z>1. Sufficient.

_________________
##### General Discussion
Senior Manager
Joined: 30 Aug 2009
Posts: 270
Location: India
Concentration: General Management
Re: DS- inequalities is Z>1?  [#permalink]

### Show Tags

14 Nov 2009, 01:56
1
RisingForceX wrote:
If x+y+z > 0, is z > 1?

(1) z > x + y +1
(2) x + y + 1 < 0

B

1. we have x+y+z >0. given z > x + y +1
let x = -12 y = 10 and z= 3 then we have x+y+z >0, z > x + y +1 and also z>1
let x = -1 y = 1/2 z=3/4 then we have x+y+z >0, z > x + y +1 but z<1. hence insuff

2. x+y+1 < 0 or x+y < -1 given that x+y+z > 0 then z>1. hence suff
Intern
Joined: 12 Jul 2016
Posts: 3
WE: Analyst (Consulting)
Re: If x + y + z > 0, is z > 1?  [#permalink]

### Show Tags

16 Jul 2016, 18:36
I think it is B because it says that

x+y+1<0 or x+y<-1 therefore,
z has to to greater than 1 for for x+y+z>0
Intern
Joined: 12 Jul 2016
Posts: 3
WE: Analyst (Consulting)
Re: If x + y + z > 0, is z > 1?  [#permalink]

### Show Tags

16 Jul 2016, 18:38
I think it is B because it says that

x+y+1<0 or x+y<-1 therefore,
z has to to greater than 1 for for x+y+z>0
CEO
Joined: 11 Sep 2015
Posts: 3241
If x + y + z > 0, is z > 1?  [#permalink]

### Show Tags

Updated on: 02 Mar 2018, 14:37
4
Top Contributor
RisingForceX wrote:
If x + y + z > 0, is z > 1?

(1) z > x + y +1
(2) x + y + 1 < 0

Target question: Is z > 1

Given: x + y + z > 0

Statement 1: z > x + y +1
Let's create a similar inequality to x + y + z > 0
Take z > x + y +1 and subtract x and y from both sides to get: z - x - y > 1
We now have two inequalities with the inequality signs facing the same direction.
z - x - y > 1
x + y + z > 0
ADD them to get: 2z > 1
Divide both sides by 2 to get: z > 1/2
So, z COULD equal 2, in which case z > 1
Or z COULD equal 3/4, in which case z < 1
Since we cannot answer the target question with certainty, statement 1 is NOT SUFFICIENT

Statement 2: x + y + 1 < 0
Let's use the same strategy.
This time, let's multiply both sides by -1 to get: -x - y - 1 > 0
We now have two inequalities with the inequality signs facing the same direction.
-x - y - 1 > 0
x + y + z > 0
ADD them to get: z - 1 > 0
Add 1 to both sides to get z > 1
Perfect!!!
Since we can answer the target question with certainty, statement 2 is SUFFICIENT

Cheers,
Brent
_________________

Test confidently with gmatprepnow.com

Originally posted by GMATPrepNow on 17 Jul 2016, 06:45.
Last edited by GMATPrepNow on 02 Mar 2018, 14:37, edited 1 time in total.
Director
Joined: 14 Nov 2014
Posts: 634
Location: India
GMAT 1: 700 Q50 V34
GPA: 3.76
Re: If x + y + z > 0, is z > 1?  [#permalink]

### Show Tags

19 Aug 2017, 20:32
1
RisingForceX wrote:
If x + y + z > 0, is z > 1?

(1) z > x + y +1
(2) x + y + 1 < 0

A.
x+y+z > 0 -------------1
z>x+y+1----------------2

x+y+2z>x+y+1
z>1/2-------------------------------A--not sufficient

B.
x+y+1<0 = -X-Y-1 > 0----------3
z>1
Suff.

Hence B
Non-Human User
Joined: 09 Sep 2013
Posts: 9197
Re: If x + y + z > 0, is z > 1?  [#permalink]

### Show Tags

26 Aug 2018, 09:51
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: If x + y + z > 0, is z > 1? &nbs [#permalink] 26 Aug 2018, 09:51
Display posts from previous: Sort by