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

 It is currently 16 Nov 2018, 12:19

### 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 November
PrevNext
SuMoTuWeThFrSa
28293031123
45678910
11121314151617
18192021222324
2526272829301
Open Detailed Calendar
• ### Free GMAT Strategy Webinar

November 17, 2018

November 17, 2018

07:00 AM PST

09:00 AM PST

Nov. 17, 7 AM PST. Aiming to score 760+? Attend this FREE session to learn how to Define your GMAT Strategy, Create your Study Plan and Master the Core Skills to excel on the GMAT.
• ### GMATbuster's Weekly GMAT Quant Quiz # 9

November 17, 2018

November 17, 2018

09:00 AM PST

11:00 AM PST

Join the Quiz Saturday November 17th, 9 AM PST. The Quiz will last approximately 2 hours. Make sure you are on time or you will be at a disadvantage.

# Is x < 0? (1) x^2 - x > 0 (2) |x| < 1

Author Message
TAGS:

### Hide Tags

Manager
Joined: 19 Nov 2017
Posts: 169
Location: India
Schools: ISB
GMAT 1: 670 Q49 V32
GPA: 4
Is x < 0? (1) x^2 - x > 0 (2) |x| < 1  [#permalink]

### Show Tags

Updated on: 29 Jul 2018, 00:21
4
00:00

Difficulty:

65% (hard)

Question Stats:

47% (01:12) correct 53% (01:10) wrong based on 59 sessions

### HideShow timer Statistics

Is $$x<0?$$ ?

(1) $$x^2 - x > 0$$

(2) $$|x| < 1$$

_________________

Regards,

Vaibhav

Sky is the limit. 800 is the limit.

~GMAC

Originally posted by vaibhav1221 on 28 Jul 2018, 20:18.
Last edited by Bunuel on 29 Jul 2018, 00:21, edited 2 times in total.
Intern
Joined: 28 Jul 2018
Posts: 6
Re: Is x < 0? (1) x^2 - x > 0 (2) |x| < 1  [#permalink]

### Show Tags

28 Jul 2018, 20:57
1
Idk what I'm doing wrong:
We need to know if X is (-) or (+)
(1) is satisfied for all numbers outside of the range 0:1 (not including 0 and 1)
(2) is satisfied for all numbers inside range -1:1 (not including -1 and 1)

So if you take (1) and (2) together, X must be a negative number between -1:0
Manager
Joined: 19 Nov 2017
Posts: 169
Location: India
Schools: ISB
GMAT 1: 670 Q49 V32
GPA: 4
Re: Is x < 0? (1) x^2 - x > 0 (2) |x| < 1  [#permalink]

### Show Tags

28 Jul 2018, 21:08
emanresu1 wrote:
Idk what I'm doing wrong:
We need to know if X is (-) or (+)
(1) is satisfied for all numbers outside of the range 0:1 (not including 0 and 1)
(2) is satisfied for all numbers inside range -1:1 (not including -1 and 1)

So if you take (1) and (2) together, X must be a negative number between -1:0

Yes you are correct in your approach. I guess i misclicked the OA as E.
Thanks. OA edited.

Posted from my mobile device
_________________

Regards,

Vaibhav

Sky is the limit. 800 is the limit.

~GMAC

MBA Section Director
Affiliations: GMATClub
Joined: 22 May 2017
Posts: 988
Concentration: Nonprofit
GPA: 4
WE: Engineering (Computer Software)
Re: Is x < 0? (1) x^2 - x > 0 (2) |x| < 1  [#permalink]

### Show Tags

28 Jul 2018, 21:12
1
To find whether x < 0

Statement 1

$$x^2 - x > 0$$

=> $$x * (x - 1) > 0$$

x can be 9 satisfying x * (x - 1) = 9 * 8 = 72 > 0

x can be -9 satisfying x * (x - 1) = (-9) * (-9-1) = (-9) * (-10) = 90 > 0

Statement 1 is not sufficient

Statement 2

|x| < 1

=> x can be 0.5 or -0.5

Statement 2 is insufficient

Combining statements 1 and 2

$$x * (x - 1) > 0$$ and |x| < 1

x * (x - 1) is positive only if x and (x-1) have same sign

Case 1

x and (x-1) are positive => x-1 > 0 => x > 1 but from statement 2 |x| < 1. So this case is not possible

Case 2

x and (x-1) are both negative and range of values for statement 2 are -1 < x < 0

=> The combined interval is -1 < x < 0 => x < 0

Statements 1 and 2 together are sufficient.

Hence option C
_________________

If you like my post press kudos +1

New project wSTAT(which Schools To Apply To?)

New - RC Butler - 2 RC's everyday

Senior Manager
Joined: 22 Feb 2018
Posts: 394
Re: Is x < 0? (1) x^2 - x > 0 (2) |x| < 1  [#permalink]

### Show Tags

28 Jul 2018, 21:17
OA : C

Question stem : Is x<0
1.$$x^2−x>0$$
$$x(x-1)>0$$
$$x$$ and $$x-1$$ both should be either positive or negative simultaneously.
This will happen if either $$x<0$$ or $$x>1$$
$$x$$ can be either +ve or -ve.
Statement 1 alone is not sufficient to answer the question: Is x<0

2: $$|x|<1$$
This implies $$-1<x<1$$
x can be either +ve or -ve.
Statement 2 alone is not sufficient to answer the question: Is x<0

Combining 1 and 2, we get $$-1<x<0$$
$$x$$ will - ve, So combining Statement 1 and Statement 2 will be sufficient to answer : Is x<0
_________________

Good, good Let the kudos flow through you

Senior DS Moderator
Joined: 27 Oct 2017
Posts: 1001
Location: India
GPA: 3.64
WE: Business Development (Energy and Utilities)
Re: Is x < 0? (1) x^2 - x > 0 (2) |x| < 1  [#permalink]

### Show Tags

29 Jul 2018, 00:31
1
See the wavy curve approach for solving inequalities:
Attachment:

WhatsApp Image 2018-07-29 at 13.57.33.jpeg [ 80.38 KiB | Viewed 461 times ]

_________________
Re: Is x < 0? (1) x^2 - x > 0 (2) |x| < 1 &nbs [#permalink] 29 Jul 2018, 00:31
Display posts from previous: Sort by