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

It is currently 22 Oct 2018, 16:23

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.

Close

Request Expert Reply

Confirm Cancel

if xy>0 and xz<0, which of the following must be true?

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Senior Manager
Senior Manager
avatar
G
Joined: 26 Dec 2015
Posts: 262
Location: United States (CA)
Concentration: Finance, Strategy
WE: Investment Banking (Venture Capital)
if xy>0 and xz<0, which of the following must be true?  [#permalink]

Show Tags

New post 28 Oct 2017, 12:09
2
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

60% (02:03) correct 40% (01:57) wrong based on 102 sessions

HideShow timer Statistics

if xy > 0 and xz < 0, which of the following must be true?

I. \(\frac{y}{z}\) < 0

II. xyz < 0

III. xy - xz > 0

A) I only

B) III only

C) I and II

D) I and III

E) II and III
PS Forum Moderator
avatar
D
Joined: 25 Feb 2013
Posts: 1216
Location: India
GPA: 3.82
GMAT ToolKit User Premium Member Reviews Badge
if xy>0 and xz<0, which of the following must be true?  [#permalink]

Show Tags

New post 28 Oct 2017, 12:27
1
LakerFan24 wrote:
if xy > 0 and xz < 0, which of the following must be true?

I. \(\frac{y}{z}\) < 0

II. xyz < 0

III. xy - xz > 0

A) I only

B) III only

C) I and II

D) I and III

E) II and III


\(xy>0\) & \(xz<0\) implies

\(x>0\), \(y>0\) & \(z<0\) ----------(1) \(OR\)

\(x<0\), \(y<0\) & \(z>0\) ----------(2)

I) as is clear from conditions (1) and (2) \(y\) & \(z\) will always have opposite signs. hence \(\frac{y}{z}<0\). True

II) from condition (1) we have \(xyz<0\) and from condition (2) we have \(xyz>0\). Hence not always true

III) \(xy>0\) & \(xz<0\) or \(-xz>0\). add both to get \(xy-xz>0\). True

Option D
Intern
Intern
avatar
B
Joined: 07 Apr 2018
Posts: 11
Re: if xy>0 and xz<0, which of the following must be true?  [#permalink]

Show Tags

New post 08 Aug 2018, 13:06
if xy > 0 and xz < 0, which of the following must be true?



I. y/z< 0 either y and x are both positive or both x and y are negative. either x or z is negative. Combining those equation means that one of z and y MUST be negative = product has to be negative

II. xyz < 0 possible scenario: x= negative, y=negative, z=positve , product will be positive!

III. xy - xz > 0 we know xy is positive, and we know xz is negative, subtract a negative number from a positive MUST produce a positive number

kudos if it helped :D
GMAT Club Bot
Re: if xy>0 and xz<0, which of the following must be true? &nbs [#permalink] 08 Aug 2018, 13:06
Display posts from previous: Sort by

if xy>0 and xz<0, which of the following must be true?

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


Copyright

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

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

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®.