If x is not equal to 0

This topic has expert replies
Master | Next Rank: 500 Posts
Posts: 186
Joined: Sat Dec 24, 2016 12:38 am
Thanked: 5 times
Followed by:3 members

If x is not equal to 0

by rsarashi » Sat May 20, 2017 9:44 pm
If x is not equal to 0, is |x| less than 1?

1) x/|x| < x


(2) |x| > x

OAC

User avatar
GMAT Instructor
Posts: 15539
Joined: Tue May 25, 2010 12:04 pm
Location: New York, NY
Thanked: 13060 times
Followed by:1906 members
GMAT Score:790

by GMATGuruNY » Sun May 21, 2017 2:35 am
Private tutor exclusively for the GMAT and GRE, with over 20 years of experience.
Followed here and elsewhere by over 1900 test-takers.
I have worked with students based in the US, Australia, Taiwan, China, Tajikistan, Kuwait, Saudi Arabia -- a long list of countries.
My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
Student Review #1
Student Review #2
Student Review #3

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 2095
Joined: Tue Dec 04, 2012 3:22 pm
Thanked: 1443 times
Followed by:247 members

by ceilidh.erickson » Sun May 21, 2017 3:08 pm
rsarashi wrote:If x is not equal to 0, is |x| less than 1?

1) x/|x| < x


(2) |x| > x

OAC
For |x| to be less than 1, x must be greater than -1 and less than 1.

Target question: -1 < x < 0 ?

(1) x/|x| < x

- If x is positive, then x/|x| = 1. So 1 < x. This would give us a "no" answer to the question.
- If x is negative, then x/|x| = -1. So -1 < x. But since x is negative, we can add: -1 < x < 0. This would give is a "yes" answer to the question.

If we get a "no" answer when x < 0 and a "yes" answer when x > 0, this is insufficient.

(2) |x| > x

If x were positive, it would be equal to |x|. So this is telling us that x must be negative. However, just knowing that it is negative is not enough to tell us whether |x| < 1. Insufficient.

Together:
Statement 2 tells us that x must be negative, so x/|x| = -1 ---> -1 < x < 0. This would give is a "yes" answer to the question.
Sufficient.

The answer is C.

Also, please always POST YOUR SOURCES. It is a copyright violation not to do so.

This question comes from Manhattan Prep CATs.
Ceilidh Erickson
EdM in Mind, Brain, and Education
Harvard Graduate School of Education