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

It is currently 25 Oct 2014, 19:08

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

Three grades of milk are 1 percent, 2 percent and 3 percent

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
1 KUDOS received
Intern
Intern
avatar
Joined: 26 Nov 2009
Posts: 14
Followers: 0

Kudos [?]: 9 [1] , given: 0

Three grades of milk are 1 percent, 2 percent and 3 percent [#permalink] New post 24 Dec 2009, 08:38
1
This post received
KUDOS
6
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  35% (medium)

Question Stats:

70% (02:56) correct 30% (01:10) wrong based on 232 sessions
Three grades of milk are 1 percent, 2 percent and 3 percent fat by volume. If x gallons of the 1 percent grade, y gallons of the 2 percent grade, and z gallons of the 3 percent grade are mixed to give x+y+z gallons of a 1.5 percent grade, what is x in terms of y and z?

A. y + 3z
B. (y +z) / 4
C. 2y + 3z
D. 3y + z
E. 3y + 4.5z
[Reveal] Spoiler: OA
Expert Post
10 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 23422
Followers: 3618

Kudos [?]: 28977 [10] , given: 2874

Re: GMAT Prep VIC Problem [#permalink] New post 24 Dec 2009, 09:23
10
This post received
KUDOS
Expert's post
3
This post was
BOOKMARKED
JimmyWorld wrote:
I got this problem wrong on the GMAT Prep and don't really understand it.

Three grades of milk are 1 percent, 2 percent and 3 percent fat by volume. If x gallons of the 1 percent grade, y gallons of the 2 percent grade, and z gallons of the 3 percent grade are mixed to give x+y+z gallons of a 1.5 percent grade, what is x in terms of y and z?
A. y + 3z
B. (y +z) / 4
C. 2y + 3z
D. 3y + z
E. 3y + 4.5z

OA is
[Reveal] Spoiler:
A


Milk concentration in mix would be 1%x+2%y+3%z and on the other hand we are told that in (x+y+z) there is 1.5% of milk. Hence:

1%x+2%y+3%z=1.5%(x+y+z) --> x+2y+3z=1.5x+1.5y+1.5z --> 0.5x=0.5y+1.5z --> x=y+3z.

Answer: A.

Hope it's clear.
_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

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; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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. ,11 Mixed Questions, 12 Fresh Meat

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., 11 New DS set.


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

Get the best GMAT Prep Resources with GMAT Club Premium Membership

3 KUDOS received
Senior Manager
Senior Manager
User avatar
Status: mba here i come!
Joined: 07 Aug 2011
Posts: 271
Location: Pakistan
Concentration: Strategy, Marketing
GMAT 1: 680 Q46 V37
GMAT 2: Q V
Followers: 24

Kudos [?]: 722 [3] , given: 48

GMAT ToolKit User
Re: GMAT Practice Test 1 PS: Ratio [#permalink] New post 15 Jan 2012, 08:46
3
This post received
KUDOS
\frac{x+2y+3z}{x+y+z} = \frac{3}{2}

x = y+3z
_________________

press +1 Kudos to appreciate posts
Download Valuable Collection of Percentage Questions (PS/DS)

3 KUDOS received
Director
Director
avatar
Joined: 28 Jul 2011
Posts: 582
Location: United States
Concentration: International Business, General Management
GPA: 3.86
WE: Accounting (Commercial Banking)
Followers: 1

Kudos [?]: 55 [3] , given: 16

Re: Three grades of milk are 1 percent, 2 percent and 3 percent [#permalink] New post 15 Jan 2012, 16:00
3
This post received
KUDOS
Its A, just put the words into equation

x+2Y+3Z=1.5(X+2Y+3Z)

X=Y+3Z

Hope it clarifies

+1 Kudos if it helps
_________________

+1 Kudos If found helpful..

Manager
Manager
avatar
Joined: 10 Jan 2010
Posts: 193
Location: Germany
Concentration: Strategy, General Management
Schools: IE '15 (M)
GMAT 1: Q V
GPA: 3
WE: Consulting (Telecommunications)
Followers: 2

Kudos [?]: 22 [0], given: 7

Re: Three grades of milk are 1 percent, 2 percent and 3 percent [#permalink] New post 22 Jan 2012, 07:04
Thanks! Sounds easy after i read your reply! Did not think through the whole question..
Expert Post
4 KUDOS received
Veritas Prep GMAT Instructor
User avatar
Joined: 16 Oct 2010
Posts: 4877
Location: Pune, India
Followers: 1157

Kudos [?]: 5383 [4] , given: 165

Re: Mixture of different grades (Milk fat by volume) [#permalink] New post 22 Jan 2012, 17:56
4
This post received
KUDOS
Expert's post
MSoS wrote:
Hi, would someone please so kind and explain the question:

Three grades of milk are 1 percent, 2 percent, and 3 percent fat by volume. If x gallons of the q percent grade, y gallons of the 2 percent grade, and z gallons of the 3 percent grade are mixed to give x + y + z gallons of a 1.5 percent grade, what is x in terms of y and z?

(a) y + 3z
(b) (y+z)/4
(c) 2y +3z
(d) 3y + z
(e) 3y + 4.5z

Thanks a lot...


A quick approach:

The question asks you for x in terms of y and z. Whatever values x, y and z can take, this relation should hold.
Since we mix 1%, 2% and 3% milk and get 1.5% milk, one way of mixing them could be that 1% and 2% are mixed in equal quantities (to give 1.5% milk) and 3% milk is not added at all. Which means x = 1, y = 1 and z = 0 should satisfy the relation between x, y and z.
The only relation that satisfies these values is (A).

Note: If multiple options satisfied these values, you could take another set of values e.g. x = 3, y = 0 and z = 1 and check out of the shortlisted options.
_________________

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

3 KUDOS received
Senior Manager
Senior Manager
avatar
Joined: 12 Mar 2012
Posts: 370
Concentration: Operations, Strategy
Followers: 2

Kudos [?]: 107 [3] , given: 31

Re: GMAT prep question 1 [#permalink] New post 22 Mar 2012, 02:16
3
This post received
KUDOS
imadkho wrote:
Three grades of milk are 1 percent, 2 percent, and 3 percent fat by volume. If x gallons of the 1 percent grade, y gallons of the 2 percent grade, and z gallons of the 3 percent grade are mixed to give x+y+z gallons of 1.5 percent grade, what is x in terms of y and z ?
A- y+3z
B- (y+z)/4
C- 2y +3z
D- 3y+z
E-3y+4.5z


0.01x+0.02y+0.03z=0.015(x+y+z)
=> x=y+3z

hence A
_________________

Practice Practice and practice...!!

If my reply /analysis is helpful-->please press KUDOS
If there's a loophole in my analysis--> suggest measures to make it airtight.

Current Student
avatar
Joined: 15 Jan 2012
Posts: 20
GMAT 1: 760 Q50 V44
GPA: 3.85
WE: Marketing (Computer Software)
Followers: 0

Kudos [?]: 8 [0], given: 2

Three grades of milk are 1 percent, 2 percent and 3 percent [#permalink] New post 10 May 2012, 10:33
Hi all,
I think I have seen a problem like this somewhere, but in DS form

If
(1) is x= y + 3z
and (2) gives you the y:z ratio
Is the second one sufficient? I somehow feel that it should be, but can't find the reasoning for that.What can we do here? pick numbers? Or is it exessive info and thus is sufficient?
sorry, I can't quote the exact second choice.
Intern
Intern
avatar
Joined: 16 Jan 2012
Posts: 4
Followers: 0

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

Three grades of milk are 1 percent, 2 percent and 3 percent [#permalink] New post 12 May 2012, 22:29
Yep this one would have seemed more obtuse to me until I realized that the percentages were meant to be for the fat content in milk.
Combining the various milk types we got a 1.5% of fat content in the resulting mixture.
Got the same answer y+3z.
Expert Post
GMAT Tutor
avatar
Joined: 20 Jul 2012
Posts: 25
GMAT 1: 780 Q50 V50
Followers: 2

Kudos [?]: 0 [0], given: 4

help need! hard weighted average question [#permalink] New post 17 Sep 2012, 16:06
Expert's post
three grades of milk are 1 percent 2 percent and 3 percent fat by volume. if x gallons of the 1 percent y gallons of the 2 percent and z gallons of the 3 percent are mixed to give x +y+z gallons of a 1.5 percent grade, what is x in terms of y and z? Thanks in advance!!!
_________________

WWW.CLEARMOUNTAINPREP.COM

Senior Manager
Senior Manager
User avatar
Joined: 13 Aug 2012
Posts: 464
Concentration: Marketing, Finance
GMAT 1: Q V0
GPA: 3.23
Followers: 16

Kudos [?]: 203 [0], given: 11

GMAT ToolKit User
Re: Three grades of milk are 1 percent, 2 percent and 3 percent [#permalink] New post 28 Sep 2012, 02:10
1%x + 2%y + 3%z = 1.5% (x+y+z)
2%y - 1.5%y + 3%z - 1.5%z = 1.5%x - 1%x
2(.5y + 1.5z = .5x)

y + 3z = x

Answer: A
_________________

Impossible is nothing to God.

Intern
Intern
avatar
Joined: 16 Jul 2012
Posts: 25
Followers: 0

Kudos [?]: 11 [0], given: 3

GMAT ToolKit User Reviews Badge
Re: Three grades of milk are 1 percent, 2 percent, and 3 percent [#permalink] New post 22 Oct 2012, 19:01
(x/100)+ (2y/100)+(3z/100) = 1.5 (x+y+z)/100 - > cancel out 100 on each side.
x+2y+3z = 1.5x+1.5y+1.5z -> bring x to one side of = sign
.5x=.5y+1.5x -> multiply by 2 on both side
x=y+3z
______________
[Reveal] Spoiler:
A
is the answer
_________________

Give me a Kudo if you find my post useful

Awesome AWA tip - how-to-get-6-0-awa-my-guide-64327.html

Amazing CR questions - 100-amazing-cr-questions-explanations-cr-700-to-800-level-137885.html

Overlapping set problems - advanced-overlapping-sets-problems-144260.html

My GMAT Story - from-530-q43-v20-to-630-q47-v30-my-gmat-story-144980.html

Manager
Manager
avatar
Joined: 11 Jan 2011
Posts: 71
GMAT 1: 680 Q44 V39
GMAT 2: 710 Q48 V40
Followers: 0

Kudos [?]: 4 [0], given: 3

GMAT ToolKit User
Re: GMAT Practice Test 1 PS: Ratio [#permalink] New post 25 Jul 2013, 13:22
MBAhereIcome wrote:
\frac{x+2y+3z}{x+y+z} = \frac{3}{2}

x = y+3z


This is essentially viewing this problem as a weighted average correct?

The mixture divided by the sum of weights?
Expert Post
Veritas Prep GMAT Instructor
User avatar
Joined: 16 Oct 2010
Posts: 4877
Location: Pune, India
Followers: 1157

Kudos [?]: 5383 [0], given: 165

Re: GMAT Practice Test 1 PS: Ratio [#permalink] New post 25 Jul 2013, 20:52
Expert's post
NvrEvrGvUp wrote:
MBAhereIcome wrote:
\frac{x+2y+3z}{x+y+z} = \frac{3}{2}

x = y+3z


This is essentially viewing this problem as a weighted average correct?

The mixture divided by the sum of weights?


Yes, it is just the weighted average of the fat concentration.
_________________

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

Intern
Intern
avatar
Joined: 18 Jun 2013
Posts: 11
Followers: 0

Kudos [?]: 1 [0], given: 3

Re: Three grades of milk are 1 percent, 2 percent and 3 percent [#permalink] New post 12 Jan 2014, 08:51
I approached it as a residuals problem

Since 1% fat = -0.5% from average
2% fat = 0.5% from average
3% fat = 1.5% from average

When added together, they have to create a 0 'residual' from 1.5% average:

-0.5x + 0.5y + 1.5z = 0
0.5y + 1.5z = 0.5x

[Reveal] Spoiler:
y + 3z = x --> A
is the answer
Manager
Manager
User avatar
Affiliations: CrackVerbal
Joined: 03 Oct 2013
Posts: 175
Location: India
GMAT 1: 780 Q51 V46
Followers: 21

Kudos [?]: 86 [0], given: 2

Re: Three grades of milk are 1 percent, 2 percent and 3 percent [#permalink] New post 12 Jan 2014, 23:27
JimmyWorld wrote:
Three grades of milk are 1 percent, 2 percent and 3 percent fat by volume. If x gallons of the 1 percent grade, y gallons of the 2 percent grade, and z gallons of the 3 percent grade are mixed to give x+y+z gallons of a 1.5 percent grade, what is x in terms of y and z?

A. y + 3z
B. (y +z) / 4
C. 2y + 3z
D. 3y + z
E. 3y + 4.5z


Using weighted average:

(x) (1) + (y) (2) + (z)(3) = (1.5) (x + y + z)

x + 2y + 3z = 1.5x + 1.5y + 1.5z
0.5y + 1.5z = 0.5x

Removing 0.5 overall:

y +3z = x
_________________

If you find our response valuable, please encourage us with Kudos!

Live online classes by 99th percentile instructors!
http://gmat.crackverbal.com/gmat-courses/online/gmat-live-course/

Get a FREE profile evaluation from CrackVerbal experts!
http://applications.crackverbal.com/free-resources/profile-evaluation/

SVP
SVP
User avatar
Joined: 06 Sep 2013
Posts: 1793
Location: United States
Concentration: Finance
GMAT 1: 710 Q48 V39
WE: Corporate Finance (Investment Banking)
Followers: 16

Kudos [?]: 202 [0], given: 310

GMAT ToolKit User
Three grades of milk are 1 percent, 2 percent and 3 percent fat [#permalink] New post 29 Jan 2014, 14:33
I solved this by using differentials

1% - x
2% - y
3% - z

So then x+y+z is also given as 1.5%, which is in fact the weighted average

Let's just play with nice numbers here

10% - x
20% - y
30% - z

x + y + z = 15%

So -5x+5y+15z = 0

X = Y + 3Z

A
Expert Post
Veritas Prep GMAT Instructor
User avatar
Joined: 16 Oct 2010
Posts: 4877
Location: Pune, India
Followers: 1157

Kudos [?]: 5383 [0], given: 165

Re: Percent / Average [#permalink] New post 29 Jan 2014, 20:22
Expert's post
Impenetrable wrote:
Three grades of milk are 1%, 2% and 3% fat by volume. If x gallons of 1%, y gallons of 2% and z gallons of 3% are mixed together to give x+y+z gallons of a 1.5%, what is x in terms of y and z?

y+3z
(y+z)/4
2y+3z
3y+z
3y+4.5z


My idea was:

(x+2y+3z)/(x+y+z) = 1.5
from here on I have no idea how to get x to one side...

Cheers,
Lars


If you develop a knack for playing with numbers, you will rarely need to make equations for ratios/percent/mixture/average problems.

What I thought here was that milk of 1% (volume x), 2% (volume y) and 3% (volume z) have to be mixed to give 1.5%. An easy way I can see immediately is that I don't take any 3% milk and mix 1% and 2% in equal quantities to get 1.5%.
i.e. If z = 0, x = y
If we put z = 0, only option (A) gives x = y hence it is the answer.
_________________

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

Re: Percent / Average   [#permalink] 29 Jan 2014, 20:22
    Similar topics Author Replies Last post
Similar
Topics:
Three grades of milk are 1 percent, 2 percent, and 3 percent chronolinkz 1 10 Dec 2007, 21:50
Three grades of milk are 1 percent, 2 percent, and 3 percent tarek99 2 07 Dec 2007, 06:21
11 Experts publish their posts in the topic Three grades of milk are 1 percent, 2 percent and 3 percent vmalaiya 15 01 Jan 2007, 06:58
Three grades of milk are 1 percent, 2 percent, and 3 percent kuristar 5 05 May 2006, 09:03
Three grades of milk are 1 percent, 2 percent, and 3 percent coffeeloverfreak 7 22 Sep 2005, 19:13
Display posts from previous: Sort by

Three grades of milk are 1 percent, 2 percent and 3 percent

  Question banks Downloads My Bookmarks Reviews Important topics  


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®.