Check GMAT Club Decision Tracker for the Latest School Decision Releases https://gmatclub.com/AppTrack

 It is currently 22 May 2017, 09:07

### 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

# For the system of equations given, what is the value of z?

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 38796
Followers: 7712

Kudos [?]: 105734 [0], given: 11578

For the system of equations given, what is the value of z? [#permalink]

### Show Tags

11 Sep 2012, 04:46
00:00

Difficulty:

5% (low)

Question Stats:

91% (01:40) correct 9% (00:36) wrong based on 774 sessions

### HideShow timer Statistics

x-4=z
y-x=8
8-z=t

For the system of equations given, what is the value of z?

(1) x = 7
(2) t = 5

Practice Questions
Question: 36
Page: 278
Difficulty: 550
[Reveal] Spoiler: OA

_________________
Math Expert
Joined: 02 Sep 2009
Posts: 38796
Followers: 7712

Kudos [?]: 105734 [1] , given: 11578

Re: For the system of equations given, what is the value of z? [#permalink]

### Show Tags

11 Sep 2012, 04:47
1
KUDOS
Expert's post
SOLUTION

x-4=z
y-x=8
8-z=t

For the system of equations given, what is the value of z?

(1) x = 7. Substitute the value of x in the first equation to find z. Sufficient.
(2) t = 5. Substitute the value of t in the third equation to find z. Sufficient.

_________________
Senior Manager
Joined: 15 Jun 2010
Posts: 361
Schools: IE'14, ISB'14, Kellogg'15
WE 1: 7 Yrs in Automobile (Commercial Vehicle industry)
Followers: 11

Kudos [?]: 398 [2] , given: 50

Re: For the system of equations given, what is the value of z? [#permalink]

### Show Tags

12 Sep 2012, 06:24
2
KUDOS
Bunuel wrote:
x-4=z
y-x=8
8-z=t

For the system of equations given, what is the value of z?

(1) x = 7
(2) t = 5

St 1: Sufficient: x=7, substituting in Eq 1, we will get value of Z, 7-4=z=3,
ST 2. Sufficient: t=5, substituting in Eq 3, We will get value of Z, 8-Z=5, Z= 3.

_________________

Regards
SD
-----------------------------
Press Kudos if you like my post.
Debrief 610-540-580-710(Long Journey): http://gmatclub.com/forum/from-600-540-580-710-finally-achieved-in-4th-attempt-142456.html

Director
Joined: 24 Aug 2009
Posts: 504
Schools: Harvard, Columbia, Stern, Booth, LSB,
Followers: 19

Kudos [?]: 732 [1] , given: 276

Re: For the system of equations given, what is the value of z? [#permalink]

### Show Tags

12 Sep 2012, 13:06
1
KUDOS
Same reasoning as above.

_________________

If you like my Question/Explanation or the contribution, Kindly appreciate by pressing KUDOS.
Kudos always maximizes GMATCLUB worth
-Game Theory

If you have any question regarding my post, kindly pm me or else I won't be able to reply

Math Expert
Joined: 02 Sep 2009
Posts: 38796
Followers: 7712

Kudos [?]: 105734 [0], given: 11578

Re: For the system of equations given, what is the value of z? [#permalink]

### Show Tags

14 Sep 2012, 06:08
SOLUTION

x-4=z
y-x=8
8-z=t

For the system of equations given, what is the value of z?

(1) x = 7. Substitute the value of x in the first equation to find z. Sufficient.
(2) t = 5. Substitute the value of t in the third equation to find z. Sufficient.

Kudos points given to everyone with correct solution. Let me know if I missed someone.
_________________
Manager
Joined: 12 Jan 2013
Posts: 220
Followers: 5

Kudos [?]: 72 [0], given: 47

Re: For the system of equations given, what is the value of z? [#permalink]

### Show Tags

18 Jul 2013, 14:58
I didnt even solve for z, all I used was the fact that "ONE unknown and TWO knowns means you can solve for the unknown".

Hence, we are given x in s(1) and that is sufficent just by looking at the top equation. Then we are given t in s(2) which is enough for the third equation.

The reason this method is superior to any other is that you quickly can move on to the next quant problem on the test, I solved this q in 35 seconds using this method.

If there are any holes in this approach, please speak up and correct me.
Current Student
Joined: 25 Sep 2012
Posts: 294
Location: India
Concentration: Strategy, Marketing
GMAT 1: 660 Q49 V31
GMAT 2: 680 Q48 V34
Followers: 2

Kudos [?]: 146 [0], given: 242

Re: For the system of equations given, what is the value of z? [#permalink]

### Show Tags

30 May 2014, 01:24
this is sub500
Intern
Joined: 10 Sep 2015
Posts: 18
Followers: 0

Kudos [?]: 1 [0], given: 19

Re: For the system of equations given, what is the value of z? [#permalink]

### Show Tags

11 Sep 2015, 00:31
Basic rule for solving linear equation

NO of Unknown === no of equation
In this question :
NO of Unknown==4
no of equation ==3

both the statements are reducing 1 unknown making the equation solvable

hence D
Target Test Prep Representative
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 886
Followers: 34

Kudos [?]: 495 [0], given: 2

Re: For the system of equations given, what is the value of z? [#permalink]

### Show Tags

09 Aug 2016, 13:49
Quote:

x-4=z
y-x=8
8-z=t

For the system of equations given, what is the value of z?

(1) x = 7
(2) t = 5

We are given 3 equations:

1) x – 4 = z

2) y – x = 8

3) 8 – z = t

We need to determine the value of z.

Statement One Alone:

x = 7

We see that we can substitute 7 for x in the first equation and then determine the value of z.

x – 4 = z

7 – 4 = z

3 = z

Statement one alone is sufficient to answer the question. We can eliminate answer choices B, C, and E.

Statement Two Alone:

t = 5

We see that we can substitute 5 for t in equation 3 and then determine the value of z.

8 – z = t

8 – z = 5

3 = z

Statement two alone is sufficient to answer the question.

_________________

Jeffery Miller

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Re: For the system of equations given, what is the value of z?   [#permalink] 09 Aug 2016, 13:49
Similar topics Replies Last post
Similar
Topics:
19 What is the value of integer z? 15 08 Jul 2016, 13:29
2 Given the linear equation y = kx + n, for what values of x w 2 08 Jun 2016, 11:39
2 What is the value of z? 6 24 Oct 2015, 07:48
9 Given the linear equation y = ax + b, for what values of x w 5 14 Jul 2016, 22:44
4 Given that X = (Y–Z)^2. What is the value of X? 5 04 May 2016, 06:52
Display posts from previous: Sort by