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

It is currently 13 Dec 2018, 08:26

R1 Admission Decisions:

Stanford Chat (Calls Started)  |  Wharton Chat  (Calls Expected Soon)  |  Fuqua Chat (Calls Expected Soon)


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
Events & Promotions in December
PrevNext
SuMoTuWeThFrSa
2526272829301
2345678
9101112131415
16171819202122
23242526272829
303112345
Open Detailed Calendar
  • The winning strategy for 700+ on the GMAT

     December 13, 2018

     December 13, 2018

     08:00 AM PST

     09:00 AM PST

    What people who reach the high 700's do differently? We're going to share insights, tips and strategies from data we collected on over 50,000 students who used examPAL.
  • GMATbuster's Weekly GMAT Quant Quiz, Tomorrow, Saturday at 9 AM PST

     December 14, 2018

     December 14, 2018

     09:00 AM PST

     10:00 AM PST

    10 Questions will be posted on the forum and we will post a reply in this Topic with a link to each question. There are prizes for the winners.

M06-06

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

Hide Tags

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 51185
M06-06  [#permalink]

Show Tags

New post 15 Sep 2014, 23:27
1
3
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

84% (01:10) correct 16% (01:31) wrong based on 110 sessions

HideShow timer Statistics

If \(y(u - c) = 0\) and \(j(u - k) = 0\), which of the following must be true, assuming \(c \lt k\)?

A. \(yj \lt 0\)
B. \(yj \gt 0\)
C. \(yj = 0\)
D. \(j = 0\)
E. \(y = 0\)

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 51185
Re M06-06  [#permalink]

Show Tags

New post 15 Sep 2014, 23:27
1
Official Solution:

If \(y(u - c) = 0\) and \(j(u - k) = 0\), which of the following must be true, assuming \(c \lt k\)?

A. \(yj \lt 0\)
B. \(yj \gt 0\)
C. \(yj = 0\)
D. \(j = 0\)
E. \(y = 0\)


\(y(u - c) = 0\). Either \(u=c\) or \(y=0\);

\(j(u - k) = 0\). Either \(u=k\) or \(j=0\);

Now, the first option (\(u=c\) and \(u=k\)) cannot be simultaneously correct for both equations because if it is, then it would mean that \(u=c=k\), but we are given that \(c \lt k\). So, only one can be correct so either \(y=0\) or \(j=0\), which makes \(yj = 0\) always true.


Answer: C
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Current Student
User avatar
B
Joined: 18 Jun 2015
Posts: 41
Reviews Badge
Re: M06-06  [#permalink]

Show Tags

New post 12 Sep 2016, 11:43
Thanks for the explanation. Somehow I missed to guess the logic of u=c and u=k can't happen simultaneously.
And got this wrong. The explanation is crisp and concise.
Intern
Intern
avatar
B
Joined: 01 Jan 2016
Posts: 2
Reviews Badge CAT Tests
Re: M06-06  [#permalink]

Show Tags

New post 26 Dec 2017, 19:39
Hello Bunuel,
besides the fact that c<k, can't it be "and/or" instead of "or" for each assumption?
y(u−c)=0. Either u=c AND/or y=0? It doesn't change the answer but I would like to know why you didn't include it in your solution. Thank you
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 51185
Re: M06-06  [#permalink]

Show Tags

New post 26 Dec 2017, 20:01
1
Guimeister wrote:
Hello Bunuel,
besides the fact that c<k, can't it be "and/or" instead of "or" for each assumption?
y(u−c)=0. Either u=c AND/or y=0? It doesn't change the answer but I would like to know why you didn't include it in your solution. Thank you


Yes it's an inclusive OR, which means that Either \(u=c\) or \(y=0\) (or both).
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

GMAT Club Bot
Re: M06-06 &nbs [#permalink] 26 Dec 2017, 20:01
Display posts from previous: Sort by

M06-06

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

Moderators: chetan2u, Bunuel



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®.