A rabbit on a controlled diet is fed daily 300 grams of a : GMAT Problem Solving (PS)
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 20 Jan 2017, 00:33

### 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

# A rabbit on a controlled diet is fed daily 300 grams of a

Author Message
TAGS:

### Hide Tags

Manager
Joined: 08 Sep 2006
Posts: 51
Followers: 0

Kudos [?]: 32 [3] , given: 0

A rabbit on a controlled diet is fed daily 300 grams of a [#permalink]

### Show Tags

26 Jul 2007, 08:45
3
KUDOS
21
This post was
BOOKMARKED
00:00

Difficulty:

15% (low)

Question Stats:

79% (02:44) correct 21% (02:00) wrong based on 1071 sessions

### HideShow timer Statistics

A rabbit on a controlled diet is fed daily 300 grams of a mixture of two foods, food X and food Y. Food X contains 10% protein and food Y contains 15% protein. If the rabbit's diet provides exactly 38 grams of protein daily, how many grams of food X are in the mixture.

A. 100
B. 140
C. 150
D. 160
E. 200
[Reveal] Spoiler: OA

Last edited by Bunuel on 06 Jun 2014, 01:39, edited 1 time in total.
Edited the question and added the OA.
Manager
Joined: 22 May 2007
Posts: 121
Followers: 1

Kudos [?]: 4 [2] , given: 0

### Show Tags

26 Jul 2007, 08:52
2
KUDOS
Set up two equations.

We know that 10%x+15%y=38 grams or .1x+.15y=38

We also know that x+y=300 grams.

2 eq. with 2 variables. Solve them and you should get it.
Director
Joined: 26 Feb 2006
Posts: 904
Followers: 4

Kudos [?]: 107 [5] , given: 0

### Show Tags

26 Jul 2007, 09:17
5
KUDOS
1
This post was
BOOKMARKED
tinman1412 wrote:
A rabbit on a controlled diet is fed daily 300 grams of a mixture of two foods, food X and food Y. Food X contains 10% protein and food Y contains 15% protein. If the rabbit's diet provides exactly 38 grams of protein daily, how many grams of food X are in the mixture.

a)100
b)140
c)150
d)160
e)200

The answer is B)140, but I do not understand the OG explanation. Can someone provide their approach to this question in detail

Thanks,

in fact one eq is enough: .1x + .15(300-x) = 38

solve for x, x = 140
Intern
Joined: 26 Aug 2006
Posts: 25
Followers: 0

Kudos [?]: 2 [1] , given: 0

### Show Tags

26 Jul 2007, 09:35
1
KUDOS
1
This post was
BOOKMARKED
tinman1412 wrote:
A rabbit on a controlled diet is fed daily 300 grams of a mixture of two foods, food X and food Y. Food X contains 10% protein and food Y contains 15% protein. If the rabbit's diet provides exactly 38 grams of protein daily, how many grams of food X are in the mixture.

a)100
b)140
c)150
d)160
e)200

The answer is B)140, but I do not understand the OG explanation. Can someone provide their approach to this question in detail

Thanks,

Much simpler method is there...
38 gms means approx. 12.66%. Then use the mixture alligation formula to calculate the ratio of X to Y, ie,

X/Y= (15-12.66)/(12.66-10)=2.33/2.66.
Hence amt of X in total mixture is 300*2.33/(2.33+2.66)=139.2~140
Senior Manager
Joined: 21 Jun 2006
Posts: 285
Followers: 1

Kudos [?]: 113 [0], given: 0

### Show Tags

26 Jul 2007, 10:16
D

Assume x grams is of mixture A and 300-x is of mixture B
Eqn is:

(300-x)*.1 + .15x = 38 (10% and 15% protein in Mixtures A and B respectively)

Solve for x =160
GMAT Club Legend
Joined: 07 Jul 2004
Posts: 5062
Location: Singapore
Followers: 30

Kudos [?]: 358 [3] , given: 0

### Show Tags

27 Jul 2007, 01:20
3
KUDOS
3
This post was
BOOKMARKED
0.1x + 0.15y = 38

x+y = 300
x = 300-y

so 0.1(300-y) + 0.15y = 38
30-0.1y + 0.15y = 38
0.05y = 8
y = 160 grams

then x = 140 grams.

Ans B
Intern
Joined: 26 Aug 2006
Posts: 25
Followers: 0

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

### Show Tags

27 Jul 2007, 04:35
tinman1412 wrote:
I was just wondering. I know there are many different ways to solve math problems, but is there a prefer method when solving Mixture Problems?

Its wat you feel comfortable with or the one which you do faster and accurately. You have to develop that approach by practice.
Atleast I think so. I solved the problem using Mixtures & Alligation formula coz I feel comfortable with that.

Sunil
Manager
Joined: 02 Jul 2007
Posts: 112
Followers: 1

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

### Show Tags

13 Aug 2009, 04:37
1
This post was
BOOKMARKED
MGMAT has a great method that has really helped me to do these problems quickly.

For mixture problems, set up a chart:

the two different mixtures go on the right hand side, the quantities of each go on the top:

Protein Other
X

Y

The problem says the two mixtures are added together to produce a new mixture totaling 300 grams, so add to the chart:

Protein Other Total
X X

Y Y

X+Y 300

Now add the information about how much protein is in each mixture

Protein Other Total
X .1X X

Y .15Y Y

X+Y 38 300

Now there are two equations with 2 variables:

.1X + .15Y=38
X + Y = 300

Simple method, but it really helps break down harder questions.
Intern
Joined: 22 Jun 2010
Posts: 9
Followers: 0

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

### Show Tags

22 Jun 2010, 16:23
can someone explain the logic of the mixture and allegation formula?

the ratio of (difference between the high value and new percentage)
over
(diff b/t high and new) + (diff b/t new and low value)

what does this ratio represent and why, when multiplying the whole to it does it give you the amount in final.....
Intern
Joined: 20 Sep 2010
Posts: 2
Followers: 0

Kudos [?]: 5 [3] , given: 0

### Show Tags

23 Sep 2010, 01:13
3
KUDOS
2
This post was
BOOKMARKED
We know that
1.00x+1.00y=300

and that
0.10x+0.15y=38

so
0.10x+0.15y=38
*10=
1.00x+1.50y=380

Align them under eachother
1.00x+1.50y=380
1.00x+1.00y=300

Means 0.50y=80
80*2=160
y=160
x=300-y
x=300-160
x=140
Intern
Joined: 07 Sep 2010
Posts: 5
Followers: 0

Kudos [?]: 6 [0], given: 0

### Show Tags

24 Sep 2010, 02:21
let x= mixture A ,, then 300-x is Mixture B

.0.1 x + (300-x)0.15=38

after the solving the equation ,,x=140
Manager
Joined: 19 Dec 2010
Posts: 145
Followers: 2

Kudos [?]: 29 [0], given: 12

### Show Tags

11 Mar 2011, 04:15
This problem is relatively easy once you break it up the way it's supposed to be broken up...

they basically say X lbs +Y lbs = 300 lbs

Now, equate the protein levels together:

0.10 X + 0.15 Y = 38

Solve
Manager
Joined: 25 May 2011
Posts: 156
Followers: 2

Kudos [?]: 60 [0], given: 71

Re: A rabbit on a controlled diet is fed daily 300 grams of a [#permalink]

### Show Tags

07 Nov 2011, 02:47
just calculation:

0.1*X+0.15*(300-X)=38
X=140
Intern
Joined: 06 Jun 2014
Posts: 1
Followers: 0

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

Re: A rabbit on a controlled diet is fed daily 300 grams of a [#permalink]

### Show Tags

06 Jun 2014, 01:27
1
KUDOS
Hi Bunuel, Pls could you update the OA here? The answer is quite obvious but the stats are skewed for lack of OA. Thanks!
Math Expert
Joined: 02 Sep 2009
Posts: 36568
Followers: 7082

Kudos [?]: 93228 [0], given: 10553

Re: A rabbit on a controlled diet is fed daily 300 grams of a [#permalink]

### Show Tags

06 Jun 2014, 01:41
1mgrnpriqp wrote:
Hi Bunuel, Pls could you update the OA here? The answer is quite obvious but the stats are skewed for lack of OA. Thanks!

_____________
Done. Thank you.
_________________
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 13459
Followers: 575

Kudos [?]: 163 [0], given: 0

Re: A rabbit on a controlled diet is fed daily 300 grams of a [#permalink]

### Show Tags

22 Jun 2015, 13:15
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.
_________________
Manager
Joined: 24 Nov 2013
Posts: 60
Followers: 0

Kudos [?]: 12 [1] , given: 115

Re: A rabbit on a controlled diet is fed daily 300 grams of a [#permalink]

### Show Tags

17 Aug 2015, 00:40
1
KUDOS
we can solve by testing answers
let qty of X be 140 gms. so Y will be 160 gms.
proteins from X = 14 gms
proteins from Y = 24 gms

so X must be 140 gms.
Current Student
Joined: 12 Aug 2015
Posts: 307
Concentration: General Management, Operations
GMAT 1: 640 Q40 V37
GMAT 2: 650 Q43 V36
GMAT 3: 600 Q47 V27
GPA: 3.3
WE: Management Consulting (Consulting)
Followers: 5

Kudos [?]: 286 [5] , given: 1474

Re: A rabbit on a controlled diet is fed daily 300 grams of a [#permalink]

### Show Tags

01 Feb 2016, 22:30
5
KUDOS
1
This post was
BOOKMARKED
30 sec reasoning out: 38/300 - is a bit less than a 13% protein content. Hence 13% is closer to 15%Y than to 10%X - this means that there is just sligthly more Y component because should those 2 be equal the protein content would have been sharply 12.5% which is not the case.

Immediately we kick out 3 answer choices >= 150 and are left with A and B. A is too low for the aboe slight deviation - so B is much closer to truth.
_________________

KUDO me plenty

Verbal Forum Moderator
Joined: 02 Aug 2009
Posts: 4225
Followers: 327

Kudos [?]: 3452 [0], given: 101

A rabbit on a controlled diet is fed daily 300 grams of a [#permalink]

### Show Tags

01 Feb 2016, 22:53
Expert's post
1
This post was
BOOKMARKED
30 sec reasoning out: 38/300 - is a bit less than a 13% protein content. Hence 13% is closer to 15%Y than to 10%X - this means that there is just sligthly more Y component because should those 2 be equal the protein content would have been sharply 12.5% which is not the case.

Immediately we kick out 3 answer choices >= 150 and are left with A and B. A is too low for the aboe slight deviation - so B is much closer to truth.

Hi,
this weighted approach,if mastered, can actually make a difference in your Quant score..
Good approach and you should try this in almost all Q that asks for an average in a mixture, or for a quantity, when an average is given..
+1 kudos
_________________

Absolute modulus :http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html

Current Student
Joined: 12 Aug 2015
Posts: 307
Concentration: General Management, Operations
GMAT 1: 640 Q40 V37
GMAT 2: 650 Q43 V36
GMAT 3: 600 Q47 V27
GPA: 3.3
WE: Management Consulting (Consulting)
Followers: 5

Kudos [?]: 286 [0], given: 1474

Re: A rabbit on a controlled diet is fed daily 300 grams of a [#permalink]

### Show Tags

01 Feb 2016, 23:14
I am going through word problem types of questions because I think i bombed this type of q in my last gmat both time-wise and accuracy wise. And what i see from OG about 30% of all questions comprise the word problem type.

During these 2 days I solved numerous word problems and here are my observations:

- very time consuming because the intuitive approach is to apply algebra and form equations, on average easy question take almost the same time as hard ones
- given my incline to make silly mistakes in algebraic calculations I should rely more on reasoning out the easy questions
- majority of easy word problems employ weighted average or mean concepts which can be done by reasoning much faster than by doing algebra - ultimately this will save at least 30 secs on each such question
-
_________________

KUDO me plenty

Re: A rabbit on a controlled diet is fed daily 300 grams of a   [#permalink] 01 Feb 2016, 23:14

Go to page    1   2    Next  [ 26 posts ]

Similar topics Replies Last post
Similar
Topics:
A bakery sells 300 baguettes and rolls daily. Each product of that bak 3 15 Sep 2016, 03:13
If the original mass of an element, in grams, is a whole number and 3 26 Apr 2016, 23:04
4 A certain rabbit population quadruples every three years. 9 11 Dec 2012, 22:06
300 Bolts 3 31 Aug 2011, 09:00
A rabbit 3 02 Mar 2011, 05:28
Display posts from previous: Sort by