GMAT Question of the Day: Daily via email | Daily via Instagram New to GMAT Club? Watch this Video

It is currently 06 Aug 2020, 02:15

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

Does x + c = y + c ?

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

Hide Tags

Find Similar Topics 
Intern
Intern
User avatar
B
Joined: 19 Sep 2012
Posts: 10
Does x + c = y + c ?  [#permalink]

Show Tags

New post 23 Mar 2017, 11:12
4
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

82% (00:28) correct 18% (00:40) wrong based on 153 sessions

HideShow timer Statistics

Does x + c = y + c ?

(1) x = y
(2) x = c
Intern
Intern
User avatar
B
Joined: 19 Sep 2012
Posts: 10
Re: Does x + c = y + c ?  [#permalink]

Show Tags

New post 23 Mar 2017, 11:18
The solution is supposed to be A. Yet, I am not clear about that.

My approach is as follows:

First, I simplify the equation: x+c=y+c, so I get x=y. The question becomes, is x=y?

Statement 1: x=y. Sufficient
Statement 2: x=c. Substituting x in the original equation we get x+x=y+x; 2x =y+x, and then x=y. So statement 2 is sufficient.

Solution is option D.

I am not sure what I am missing.
Board of Directors
User avatar
P
Joined: 17 Jul 2014
Posts: 2420
Location: United States (IL)
Concentration: Finance, Economics
GMAT 1: 650 Q49 V30
GPA: 3.92
WE: General Management (Transportation)
GMAT ToolKit User Reviews Badge
Re: Does x + c = y + c ?  [#permalink]

Show Tags

New post 23 Mar 2017, 11:25
3
racingip wrote:
The solution is supposed to be A. Yet, I am not clear about that.

My approach is as follows:

First, I simplify the equation: x+c=y+c, so I get x=y. The question becomes, is x=y?

Statement 1: x=y. Sufficient
Statement 2: x=c. Substituting x in the original equation we get x+x=y+x; 2x =y+x, and then x=y. So statement 2 is sufficient.

Solution is option D.

I am not sure what I am missing.


you are not correct, and I will provide few examples.

statement 1 is sufficient as you say.
x=y, that means c=c all the times
say x=2, y=2, c=-2
2-2=2-2 = always true.

statement 2 is not sufficient, and here is why:
case 1:
x=c
x=2, c=2, y=2
2+2=2+2 - true

case 2:
x=c
x=2, c=2. y=-2
2+2=y+2 - not true
Y can be ANY number, therefore, it's an additional coefficient that we don't know

A is the answer.

don't take the QUESTION as a statement - you are asked whether x+c=y+c, not given it as a FACT!
Director
Director
avatar
S
Joined: 12 Nov 2016
Posts: 663
Location: United States
Schools: Yale '18
GMAT 1: 650 Q43 V37
GRE 1: Q157 V158
GPA: 2.66
Does x + c = y + c ?  [#permalink]

Show Tags

New post 22 May 2017, 16:48
racingip wrote:
The solution is supposed to be A. Yet, I am not clear about that.

My approach is as follows:

First, I simplify the equation: x+c=y+c, so I get x=y. The question becomes, is x=y?

Statement 1: x=y. Sufficient
Statement 2: x=c. Substituting x in the original equation we get x+x=y+x; 2x =y+x, and then x=y. So statement 2 is sufficient.

Solution is option D.

I am not sure what I am missing.


You're making the mistake of already assuming what you're attempting to prove either incorrect or correct in the problem. Be careful- this is a huge trap on data sufficiency; you can only reduce the equation in the stimulus to x=c if the stated equation x + c = y + c is already known to be true.
Senior Manager
Senior Manager
User avatar
P
Joined: 07 Jul 2012
Posts: 354
Location: India
Concentration: Finance, Accounting
GPA: 3.5
Re: Does x + c = y + c ?  [#permalink]

Show Tags

New post 22 May 2017, 19:14
(1) x=y, add C on both sides of the equation
x+c= y+c [Suff]
(2) x=c, if x=y then answer is yes
if x>y then answer is no.Two different answer, [Insuff]

Answer: A.

Kudos please if you like my explanation!
GMAT Club Legend
GMAT Club Legend
User avatar
V
Joined: 11 Sep 2015
Posts: 4999
Location: Canada
GMAT 1: 770 Q49 V46
Re: Does x + c = y + c ?  [#permalink]

Show Tags

New post 17 Apr 2019, 06:44
1
Top Contributor
racingip wrote:
Does x + c = y + c ?

(1) x = y
(2) x = c


Target question: Does x + c = y + c ?
This is a good candidate for rephrasing the target question.
Take the equation x + c = y + c, and subtract c from both sides to get: x = y

REPHRASED target question: Does x = y ?

Aside: the video below has tips on rephrasing the target question

Statement 1: x = y
Perfect!The answer to the REPHRASED target question is YES, x = y
Since we can answer the REPHRASED target question with certainty, statement 1 is SUFFICIENT

Statement 2: x = c
Since we know nothing about the value of y, we cannot answer the REPHRASED target question
Statement 2 is NOT SUFFICIENT

Answer: A

Cheers,
Brent

RELATED VIDEO FROM MY COURSE

_________________
If you enjoy my solutions, you'll love my GMAT prep course.

Image
Non-Human User
User avatar
Joined: 09 Sep 2013
Posts: 15603
Re: Does x + c = y + c ?  [#permalink]

Show Tags

New post 11 Jul 2020, 20:01
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 Club Bot
Re: Does x + c = y + c ?   [#permalink] 11 Jul 2020, 20:01

Does x + c = y + c ?

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





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