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

It is currently 21 May 2013, 06:49
Customize  |  Hide

m10 Q02

  Question banks Downloads My Bookmarks Reviews  
Author Message
Manager
Manager
Status: And the Prep starts again...
Joined: 03 Aug 2010
Posts: 139
Followers: 1

Kudos [?]: 20 [0], given: 20

GMAT Tests User
m10 Q02 [#permalink] New post 22 Apr 2012, 23:57
00:00

Question Stats:

66% (02:34) correct 33% (02:26) wrong based on 0 sessions
If 2X + 3Y = 12 , what is X ?

1) X = 6 - (\frac{3}{2})Y
2) Y = 4 - (\frac{3}{2})X

Why is statement 1 not sufficient?

Can I not find the value of Y and substitute in 2X + 3Y = 12. I did this, please tell me what mistake I am making

2X = 12-3Y
From Statement 1 X = 6 - (\frac{3}{2})Y
Which can be simplified to X = (\frac{9}{2})Y
Therefore, Y = (\frac{2}{9})X

Now if i can substitute this Y in 2X = 12-3Y
2X = 12-\frac{6}{9}X
2X = 12-\frac{2}{3}X
2X+\frac{2}{3}X = 12
\frac{8X}{3} = 12
8X = 36
X = \frac{36}{8}
[Reveal] Spoiler: OA

_________________

My First Blog on my GMAT Journey

Arise, Awake and Stop not till the goal is reached

GMAT Club team member
User avatar
Joined: 02 Sep 2009
Posts: 11533
Followers: 1795

Kudos [?]: 9553 [0], given: 826

Re: m10 Q02 [#permalink] New post 23 Apr 2012, 00:35
ENAFEX wrote:
If 2X + 3Y = 12 , what is X ?

1) X = 6 - (\frac{3}{2})Y
2) Y = 4 - (\frac{3}{2})X

Why is statement 1 not sufficient?

Can I not find the value of Y and substitute in 2X + 3Y = 12. I did this, please tell me what mistake I am making

2X = 12-3Y
From Statement 1 X = 6 - (\frac{3}{2})Y
Which can be simplified to X = (\frac{9}{2})Y
Therefore, Y = (\frac{2}{9})X

Now if i can substitute this Y in 2X = 12-3Y
2X = 12-\frac{6}{9}X
2X = 12-\frac{2}{3}X
2X+\frac{2}{3}X = 12
\frac{8X}{3} = 12
8X = 36
X = \frac{36}{8}


The red part is not correct: x = 6 - \frac{3}{2}y --> x=\frac{12-3y}{2}, not x=\frac{9}{2}y

If 2x + 3y = 12, what is x ?

(1) x = 6 - (\frac{3}{2})y --> multiply both parts by 2: 2x=12-3y --> rearrange: 2x + 3y = 12, so we have the same equation as in the stem. Not sufficient.

(2) y = 4 - (\frac{3}{2})x --> 2y=8-3x --> 3x+2y=8. We have two distinct linear equations, hence we can get the single numerical value of x. Sufficient.

Answer: B.
_________________

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory

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. NEW!!!

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. NEW!!!


What are GMAT Club Tests?
25 extra-hard Quant Tests

Find out what's new at GMAT Club - latest features and updates

Manager
Manager
Status: And the Prep starts again...
Joined: 03 Aug 2010
Posts: 139
Followers: 1

Kudos [?]: 20 [0], given: 20

GMAT Tests User
Re: m10 Q02 [#permalink] New post 23 Apr 2012, 03:22
That was silly!!

Sorry to waste your time. :D GGRRR
_________________

My First Blog on my GMAT Journey

Arise, Awake and Stop not till the goal is reached

Re: m10 Q02   [#permalink] 23 Apr 2012, 03:22
    Similar topics Author Replies Last post
Similar
Topics:
Popular new posts 11 M10 #04 gameCode 10 05 Nov 2008, 13:13
Popular new posts 19 EXPERTS_POSTS_IN_THIS_TOPIC m10 Q13 smarinov 16 20 Dec 2008, 16:42
Popular new posts 18 M10 Q35 gk2k2 24 21 Dec 2008, 11:13
New posts EXPERTS_POSTS_IN_THIS_TOPIC M08: q02 zisis 3 11 Nov 2010, 12:08
New posts m01q02 bholakc 1 14 Sep 2011, 05:09
Display posts from previous: Sort by

m10 Q02

  Question banks Downloads My Bookmarks Reviews  

Moderator: Bunuel



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®.