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

It is currently 01 Feb 2015, 09:11

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

Is x/p(p 2 + q 2 + r 2 ) = x

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Expert Post
Moderator
Moderator
User avatar
Joined: 01 Sep 2010
Posts: 2511
Followers: 376

Kudos [?]: 3069 [0], given: 713

Is x/p(p 2 + q 2 + r 2 ) = x [#permalink] New post 03 Feb 2013, 17:45
Expert's post
2
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

76% (02:44) correct 24% (02:26) wrong based on 50 sessions
Expert Post
1 KUDOS received
Veritas Prep GMAT Instructor
User avatar
Joined: 16 Oct 2010
Posts: 5156
Location: Pune, India
Followers: 1253

Kudos [?]: 6088 [1] , given: 173

Re: Is x/p(p 2 + q 2 + r 2 ) = x [#permalink] New post 03 Feb 2013, 21:46
1
This post received
KUDOS
Expert's post
carcass wrote:
Is \frac{x}{p} (p 2 + q 2 + r 2 ) = xp + yq + zr?

(1) q^2 = r^2

(2) yq = zr


There are too many variables here so let's focus on logic.

Is \frac{x}{p} (p 2 + q 2 + r 2 ) = xp + yq + zr?
Is xp + \frac{x}{p}(q 2 + r 2 ) = xp + yq + zr?
Is \frac{x}{p}(q 2 + r 2 ) = yq + zr?

(1) q^2 = r^2
Even if q^2 = r^2, there are lots of other variables e.g. x, y and z which can take different values to make the two sides unequal. But if q = r = 0, the two sides become equal so not sufficient alone.

(2) yq = zr
Again, there are no constraints on x and p and they can take different values to make the two sides of the equation unequal. But if q = r = 0, the two sides become equal so not sufficient alone.

Using both together, there are still no constraints on the values x and p can take so the two sides needn't be equal. But if q = r = 0, the two sides become equal so not sufficient.

Answer (E)
_________________

Karishma
Veritas Prep | GMAT Instructor
My Blog

Save $100 on Veritas Prep GMAT Courses And Admissions Consulting
Enroll now. Pay later. Take advantage of Veritas Prep's flexible payment plan options.

Veritas Prep Reviews

Expert Post
Moderator
Moderator
User avatar
Joined: 01 Sep 2010
Posts: 2511
Followers: 376

Kudos [?]: 3069 [0], given: 713

Re: Is x/p(p 2 + q 2 + r 2 ) = x [#permalink] New post 04 Feb 2013, 03:59
Expert's post
Moderator
Moderator
User avatar
Joined: 10 May 2010
Posts: 823
Followers: 22

Kudos [?]: 332 [0], given: 191

GMAT ToolKit User Premium Member
Re: Is x/p(p 2 + q 2 + r 2 ) = x [#permalink] New post 04 Feb 2013, 13:16
What additional condition must be present for the equation to be true ?

[Reveal] Spoiler:
xq = yp

_________________

The question is not can you rise up to iconic! The real question is will you ?

CEO
CEO
User avatar
Joined: 09 Sep 2013
Posts: 3907
Followers: 253

Kudos [?]: 49 [0], given: 0

Premium Member
Re: Is x/p(p 2 + q 2 + r 2 ) = x [#permalink] New post 13 Jan 2015, 12:39
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Director
Director
User avatar
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 598
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: 340 Q170 V170
Followers: 20

Kudos [?]: 114 [0], given: 9

Re: Is x/p(p 2 + q 2 + r 2 ) = x [#permalink] New post 13 Jan 2015, 12:56
Hi All,

DS questions rarely involve this many variables, but when a DS question is this "crazy looking" the solution can usually be found by TESTing VALUES and keeping everything really 'simple'

Here, we're asked if (X/P)(P^2 + Q^2 + R^2) = XP + YQ + ZR. This is a YES/NO question.

The first thing that you should notice is that the variables Y and Z only appear on the right side of the equation/question. Their respective values will have a great impact on whether the answer to the question is YES or NO.

Fact 1: Q^2 = R^2

Let's TEST VALUES (and keep it simple!)

IF....
EVERY variable = 0, then the answer to the question is YES.

IF.....
X, P, Q and R = 1
Y = Z = 2, then the answer to the question is NO.
Fact 1 is INSUFFICIENT

Fact 2: YQ = ZR

Notice how BOTH TESTs from Fact 1 ALSO fit Fact 2.....This gives us a YES answer and a NO answer here as well.
Fact 2 is INSUFFICIENT

Combined, we have the same two TESTs that fit BOTH Facts and provide 2 different answers.
Combined, INSUFFICIENT

Final Answer:
[Reveal] Spoiler:
E


GMAT assassins aren't born, they're made,
Rich
_________________

Rich Cohen
Rich.C@empowergmat.com
http://www.empowergmat.com

Re: Is x/p(p 2 + q 2 + r 2 ) = x   [#permalink] 13 Jan 2015, 12:56
    Similar topics Author Replies Last post
Similar
Topics:
Is rs=rx-2? 1. r is odd 2. x=s+2 agnok 2 17 May 2010, 12:44
R = 1-2xy+x2y2 zz0vlb 2 27 Apr 2010, 05:43
X^2-5*X+N = R R^2-5*R+N = Q If R,X # 0 and N is a positive KillerSquirrel 4 27 Jun 2007, 00:31
If r = q^2 and r does not equal 0, is r > q? (1) -(r*q)/2 duttsit 8 13 Nov 2005, 20:54
If P^2 - Q^2 = 10, Q^2 + PR = 10, R^2 + PQ = 10, and R Titleist 6 01 Nov 2005, 13:58
Display posts from previous: Sort by

Is x/p(p 2 + q 2 + r 2 ) = x

  Question banks Downloads My Bookmarks Reviews Important topics  


cron

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®.