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

 It is currently 17 Jun 2018, 15:22

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# What is the value of x?

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 46035
What is the value of x? [#permalink]

### Show Tags

10 Nov 2014, 08:29
2
00:00

Difficulty:

5% (low)

Question Stats:

77% (00:44) correct 23% (00:35) wrong based on 140 sessions

### HideShow timer Statistics

Tough and Tricky questions: Sequences.

What is the value of x?

(1) 2x - 5y + 6 = 12

(2) 8x - (4x + 10y) + 27 = 39

Kudos for a correct solution.

_________________
Retired Moderator
Joined: 17 Sep 2013
Posts: 370
Concentration: Strategy, General Management
GMAT 1: 730 Q51 V38
WE: Analyst (Consulting)
Re: What is the value of x? [#permalink]

### Show Tags

10 Nov 2014, 08:47
1
Both equations are of the same line...So we can't make out the value of x..it can be anywhere over the line 2x-5y-6=0

So it should be E..??
_________________

Appreciate the efforts...KUDOS for all
Don't let an extra chromosome get you down..

Manager
Joined: 10 Sep 2014
Posts: 98
Re: What is the value of x? [#permalink]

### Show Tags

10 Nov 2014, 11:37
I see that people are posting E so maybe I am missing something but I liked option C. Since we need a value for X, each statement alone will be insufficient since they each have 2 variables and you cannot get 1 of them to a single value. Since each statement only has 2 variables and they are x and y, we can combine them to get a value for x. Answer C!
Manager
Joined: 05 Jun 2014
Posts: 67
GMAT 1: 630 Q42 V35
Re: What is the value of x? [#permalink]

### Show Tags

11 Nov 2014, 02:08
2
Eq 1 and 2 are insuff alone as they inclide two variables and its impossible to solve for one variable i.e x. Combined they provide the same info, so nothing new. Answer should be E.
Intern
Joined: 10 Mar 2014
Posts: 37
Concentration: General Management, Technology
GMAT 1: 650 Q47 V32
GPA: 4
Re: What is the value of x? [#permalink]

### Show Tags

11 Nov 2014, 05:13
1
(1) 2x - 5y + 6 = 12 => 2x - 5y = 6

(2) 8x - (4x + 10y) + 27 = 39 => 4x - 10y = 12 or 2 (2x -5y ) = 2* 6

Since both equation are same, x can not be determined, hence E
Intern
Joined: 04 Jul 2014
Posts: 46
Schools: Smeal" 20
Re: What is the value of x? [#permalink]

### Show Tags

14 Nov 2014, 00:40
1
Bunuel wrote:

Tough and Tricky questions: Sequences.

What is the value of x?

(1) 2x - 5y + 6 = 12

(2) 8x - (4x + 10y) + 27 = 39

Kudos for a correct solution.

S1 : 2x-5y = 6....can have many different values of x & Y e.g. X=8, Y=2 is one solution ; x=13, Y=4 is another one. Hence S1 is insufficient.

S2 : 4x-10y = 12 ....the equation is the same as S1 [multiplied by 2]. Hence S2 is insufficient.

Since both equations are same, we can't solve for X & Y using these two equations. Hence taking S1 & S2 together is also insufficient.

Current Student
Joined: 02 Sep 2014
Posts: 89
Location: United States
Schools: Haas EWMBA '20
GMAT 1: 770 Q50 V44
GPA: 3.97
Re: What is the value of x? [#permalink]

### Show Tags

14 Nov 2014, 00:48
Bunuel wrote:

Tough and Tricky questions: Sequences.

What is the value of x?

(1) 2x - 5y + 6 = 12

(2) 8x - (4x + 10y) + 27 = 39

Kudos for a correct solution.

I agree it is E as well. Both equations are same so x cannot be solved.
Intern
Joined: 17 Jul 2013
Posts: 38
Location: India
WE: Information Technology (Health Care)
Re: What is the value of x? [#permalink]

### Show Tags

14 Nov 2014, 00:54
IMO E

both are same equations when simplified

OA?
_________________

I'm on 680... 20 days to reach 700 +

Director
Joined: 12 Nov 2016
Posts: 776
Location: United States
Schools: Yale '18
GMAT 1: 650 Q43 V37
GRE 1: 315 Q157 V158
GPA: 2.66
Re: What is the value of x? [#permalink]

### Show Tags

08 Sep 2017, 18:39
1
Bunuel wrote:

Tough and Tricky questions: Sequences.

What is the value of x?

(1) 2x - 5y + 6 = 12

(2) 8x - (4x + 10y) + 27 = 39

Kudos for a correct solution.

The parentheses is just here to confuse you

8x-4x +10y= 12
4x-2x =10y =6
2x -5y =6

redundant info

E
Director
Joined: 12 Nov 2016
Posts: 776
Location: United States
Schools: Yale '18
GMAT 1: 650 Q43 V37
GRE 1: 315 Q157 V158
GPA: 2.66
Re: What is the value of x? [#permalink]

### Show Tags

10 Sep 2017, 13:03
1
Bunuel wrote:

Tough and Tricky questions: Sequences.

What is the value of x?

(1) 2x - 5y + 6 = 12

(2) 8x - (4x + 10y) + 27 = 39

Kudos for a correct solution.

The subtle trick played here is redundant information- the questions asks for the value of X, specifically.

St 1

2x-5y= 6

insuff

St 2

8x-4x-10y =12
4x- 10y= 12
2(2x-5y) =12
(2x-5y) =6

No better than st 1

insuff

St 1 & 2

Insuff because both statements give us the same thing

E
CEO
Joined: 12 Sep 2015
Posts: 2557
Re: What is the value of x? [#permalink]

### Show Tags

11 Sep 2017, 14:12
Top Contributor
Bunuel wrote:

Tough and Tricky questions: Sequences.

What is the value of x?

(1) 2x - 5y + 6 = 12

(2) 8x - (4x + 10y) + 27 = 39

Kudos for a correct solution.

Target question: What is the value of x?

Statement 1: 2x - 5y + 6 = 12
Subtract 6 from both sides to get: 2x - 5y = 6
Since we have one equation with 2 variables, there are infinitely many solutions.
In other words, x can have infinitely many values, which means statement 1 is NOT SUFFICIENT.

ASIDE: If you're not 100% convinced that there are infinitely many solutions, you can always test some values
There are several values of x and y that satisfy the equation 2x - 5y = 6. Here are two:
Case a: x = 3 and y = 0, in which case x = 3
Case b: x = 8 and y = 2, in which case x = 8

Statement 2: 8x - (4x + 10y) + 27 = 39
Subtract 27 from both sides to get: 8x - (4x + 10y) = 12
Expand: 8x - 4x - 10y = 12
Simplify: 4x - 10y = 12
Here we have another equation with 2 variables, which means there are infinitely many solutions.
In other words, x can have infinitely many values, which means statement 2 is NOT SUFFICIENT.

Statements 1 and 2 combined
Statement 1 tells us that 2x - 5y = 6
Statement 2 tells us that 4x - 10y = 12
IMPORTANT: the two equations above are EQUIVALENT equations.
If we take the equation 4x - 10y = 12 and divide both sides by 2 we get the EQUIVALENT equation 2x - 5y = 6
Since the two statements provide the same information, and since each statement alone is NOT SUFFICIENT, we can conclude that the COMBIEND statements are NOT SUFFICIENT

RELATED VIDEO

_________________

Brent Hanneson – Founder of gmatprepnow.com

Re: What is the value of x?   [#permalink] 11 Sep 2017, 14:12
Display posts from previous: Sort by