Find all School-related info fast with the new School-Specific MBA Forum

It is currently 23 Oct 2014, 03:46

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

If x>y>z, is xz>0? 1) xy<0 2) yz>0

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
SVP
SVP
avatar
Joined: 14 Dec 2004
Posts: 1709
Followers: 1

Kudos [?]: 37 [0], given: 0

If x>y>z, is xz>0? 1) xy<0 2) yz>0 [#permalink] New post 19 Mar 2006, 06:02
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
If x>y>z, is xz>0?

1) xy<0
2) yz>0
Manager
Manager
User avatar
Joined: 22 Apr 2005
Posts: 129
Location: Los Angeles
Followers: 1

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

 [#permalink] New post 19 Mar 2006, 06:13
1. xy < 0 => ((x < 0) && (y > 0)) || ((x > 0) && (y < 0)) with given x>y>z => ((x > 0) && (y < 0)) => z < 0 => xz < 0

2. ((y > 0) && (z > 0)) || ((y < 0) && (z < 0)) with ((y < 0) && (z < 0)) we can't say anything about x.

A
VP
VP
User avatar
Joined: 29 Dec 2005
Posts: 1351
Followers: 7

Kudos [?]: 28 [0], given: 0

 [#permalink] New post 19 Mar 2006, 07:06
Tyr wrote:
1. xy < 0 => ((x < 0) && (y > 0)) || ((x > 0) && (y < 0)) with given x>y>z => ((x > 0) && (y < 0)) => z < 0 => xz < 0

2. ((y > 0) && (z > 0)) || ((y < 0) && (z < 0)) with ((y < 0) && (z < 0)) we can't say anything about x.

A


altho, i did not follow your explanation, agree with you answer as A.
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 07 Jul 2004
Posts: 5095
Location: Singapore
Followers: 19

Kudos [?]: 155 [0], given: 0

 [#permalink] New post 19 Mar 2006, 07:07
1) xY < 0

Could be x positive, y negative and z negative then xz = negative (E.g x = 10, y = -1, z = -10)
Or x negative, y negative and z negative then xz = positive (E.g x = -1, y = -2, z = -3)

Insufficient.

2) yz > 0.

Could be y positive, z positive, then xz would be positive (E.g. y = 10, z = 5 and x > 10)
Or y negative, z negative, then xz would be negative/positive. (E.g. y = -3, z = -5 and x > -3)

Insufficient.

Using 1) and 2)

Could be y negative, z negative, then x must be positive and xz = negative
or
Could be y positive, z positive, then x must be negative (Does not hold since x > y)

Ans C
Manager
Manager
avatar
Joined: 23 Jan 2006
Posts: 193
Followers: 1

Kudos [?]: 2 [0], given: 0

 [#permalink] New post 19 Mar 2006, 07:13
I say A.

ywilfred wrote:
1) xY < 0

Could be x positive, y negative and z negative then xz = negative (E.g x = 10, y = -1, z = -10)
Or x negative, y negative and z negative then xz = positive (E.g x = -1, y = -2, z = -3)

Insufficient.

2) yz > 0.

Could be y positive, z positive, then xz would be positive (E.g. y = 10, z = 5 and x > 10)
Or y negative, z negative, then xz would be negative/positive. (E.g. y = -3, z = -5 and x > -3)

Insufficient.

Using 1) and 2)

Could be y negative, z negative, then x must be positive and xz = negative
or
Could be y positive, z positive, then x must be negative (Does not hold since x > y)

Ans C


This can't be if xy < 0. either one could be negative, but not both. (but from given information, we know that x>y, so x is positive and y is negative)
Manager
Manager
User avatar
Joined: 22 Apr 2005
Posts: 129
Location: Los Angeles
Followers: 1

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

 [#permalink] New post 20 Mar 2006, 02:51
ywilfred wrote:
1) xY < 0

Could be x positive, y negative and z negative then xz = negative (E.g x = 10, y = -1, z = -10)
Or x negative, y negative and z negative then xz = positive (E.g x = -1, y = -2, z = -3)

Insufficient.


"Or x negative, y negative" negative * negative = positive // flaw.
  [#permalink] 20 Mar 2006, 02:51
    Similar topics Author Replies Last post
Similar
Topics:
Is x^7*y^2*z^3 > 0 ? (1) yz < 0 (2) xz > 0 fxsunny 0 12 Sep 2013, 02:18
17 Experts publish their posts in the topic Is (x^7)(y^2)(z^3) > 0 ? (1) yz < 0 (2) xz > 0 TheGmatTutor 28 10 Jun 2010, 11:52
5 If xyz > 0, is x > 0? (1) xy > 0 (2) xz > 0 DestinyChild 8 10 Jan 2010, 18:31
If xyz > 0, is x>0? 1) xy> 0 2) xz>0 jlui4477 3 24 Feb 2006, 19:04
If xyz > 0, is x > 0? (1) xy > 0 (2) xz > 0 TeHCM 7 17 Dec 2005, 22:49
Display posts from previous: Sort by

If x>y>z, is xz>0? 1) xy<0 2) yz>0

  Question banks Downloads My Bookmarks Reviews Important topics  


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®.