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

 It is currently 20 Feb 2019, 14:02

### 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 February
PrevNext
SuMoTuWeThFrSa
272829303112
3456789
10111213141516
17181920212223
242526272812
Open Detailed Calendar
• ### Free GMAT Prep Hour

February 20, 2019

February 20, 2019

08:00 PM EST

09:00 PM EST

Strategies and techniques for approaching featured GMAT topics. Wednesday, February 20th at 8 PM EST

February 21, 2019

February 21, 2019

10:00 PM PST

11:00 PM PST

Kick off your 2019 GMAT prep with a free 7-day boot camp that includes free online lessons, webinars, and a full GMAT course access. Limited for the first 99 registrants! Feb. 21st until the 27th.

# Each piglet in a litter is fed exactly one-half pound of a mixture of

Author Message
TAGS:

### Hide Tags

Senior Manager
Joined: 02 Apr 2014
Posts: 476
Location: India
Schools: XLRI"20
GMAT 1: 700 Q50 V34
GPA: 3.5
Re: Each piglet in a litter is fed exactly one-half pound of a mixture of  [#permalink]

### Show Tags

19 Feb 2018, 00:47
Great Question.
Let n = number of piglets.
Let 4x = total oats in pounds, 6y = total barley in pounds
Piglet A: $$x(1/4th) + y(1/6th) = 1.5$$ ----(1)
Remaining piglets: $$3x + 5y = 1.5(n-1)$$
= $$3x + 3y + 2y = 1.5n - 1.5$$
= 3(x+y) + 2y = 1.5n - 1.5
= $$3(1.5) + 2y = 1.5n - 1.5$$ (from --(1))
= $$1.5n = 6 + 2y$$
= $$n = 2(y+3)/1.5$$
=> $$n = 4(y+3)/3$$
Now note, n is an integer, also we have 4, (y+3)/3 which is a fraction,
multiplication of 4 and (y+3)/3 a fraction can yield integer, only if the fraction is multiple of 1.25
if $$(y+3)/3$$ = 1.25 => y = 0.75
if $$(y+3)/3$$ = 2.5 => y = 4.5 (but y cannot be greater than 1.5)
also y cannot be zero and make (y+3)/3 = 1 ((as given prompt, each piglet is fed some grain))
so $$(y+3)/3$$ must be 1.25 and n = 5 => sufficient (C)
Manager
Joined: 10 Apr 2018
Posts: 182
Re: Each piglet in a litter is fed exactly one-half pound of a mixture of  [#permalink]

### Show Tags

12 Sep 2018, 11:26
hellosanthosh2k2 wrote:
Great Question.
Let n = number of piglets.
Let 4x = total oats in pounds, 6y = total barley in pounds
Piglet A: $$x(1/4th) + y(1/6th) = 1.5$$ ----(1)
Remaining piglets: $$3x + 5y = 1.5(n-1)$$
= $$3x + 3y + 2y = 1.5n - 1.5$$
= 3(x+y) + 2y = 1.5n - 1.5
= $$3(1.5) + 2y = 1.5n - 1.5$$ (from --(1))
= $$1.5n = 6 + 2y$$
= $$n = 2(y+3)/1.5$$
=> $$n = 4(y+3)/3$$
Now note, n is an integer, also we have 4, (y+3)/3 which is a fraction,
multiplication of 4 and (y+3)/3 a fraction can yield integer, only if the fraction is multiple of 1.25
if $$(y+3)/3$$ = 1.25 => y = 0.75
if $$(y+3)/3$$ = 2.5 => y = 4.5 (but y cannot be greater than 1.5)
also y cannot be zero and make (y+3)/3 = 1 ((as given prompt, each piglet is fed some grain))
so $$(y+3)/3$$ must be 1.25 and n = 5 => sufficient (C)

Hello hellosanthosh2k2,

How did u get this $$x(1/4th) + y(1/6th) = 1.5$$ . shouldn't it be 0.5.

Well i used a approach similar to yours, here is what i did

Say total piglets is x

say piglet a was fed$$\frac{1}{4}$$ of and$$\frac{1}{6}$$ of , then each piglet was fed$$\frac{1}{4}$$+$$\frac{1}{6}$$ = $$\frac{5}{12}.$$

Remaining food is$$\frac{3}{4}+\frac{5}{6}$$ =$$\frac{19}{12}$$

So the Remaining food was equally divided among (x-1) piglets with each getting $$\frac{5}{12}$$

so $$\frac{5}{12}* (x-1)= \frac{19}{12)$$

So x is some value.
Hence C is sufficient.

Probus
Intern
Joined: 16 Sep 2012
Posts: 13
Re: Each piglet in a litter is fed exactly one-half pound of a mixture of  [#permalink]

### Show Tags

15 Sep 2018, 04:42
Let's say ratio of oats to total mixture in each piglet A,B,C,D,... be a,b,c,d,.. respectively.
considering condition 1 : (1/2)*a=(1/4)*[(1/2)*(a)+(1/2)*(b)+...so on]
this equation gets down to 3a=b+c+d+..so on -------------(I)
this equation does not restrict us to any number of piglets so condition 1 by itself is not sufficient

considering only condition 2: on similar lines
(1/2)*(1-a)=(1/6)*[(1/2)*(1-a)+(1/2)*(1-b)+...so on]
5(1-a)=(1-b)+(1-c)+...so on -------------------(II)
this equation does not restrict us to any number of piglets so condition 2 by itself is not sufficient
5-2a=[b+c+d+..so on]+[(1-b)+(1-c)+...so on]=1+1+1+1+..so on
As R.H.S of above equation is an integer, L.H.S of above equation gives a=1/2
So there are 5 piglets.
Intern
Joined: 05 Oct 2017
Posts: 1
Re: Each piglet in a litter is fed exactly one-half pound of a mixture of  [#permalink]

### Show Tags

21 Nov 2018, 01:47

solving the problem like this, you are assuming that all the grains available must be fed to piglets. This is not highlighted in the question stem. If this assumption were relaxed, you cannot be sure about the total amount of piglets (which can be from 1 to 5).

What am I getting wrong?

Thank you very much!
Veritas Prep GMAT Instructor
Joined: 16 Oct 2010
Posts: 8888
Location: Pune, India
Re: Each piglet in a litter is fed exactly one-half pound of a mixture of  [#permalink]

### Show Tags

21 Nov 2018, 20:30
Leuro wrote:

solving the problem like this, you are assuming that all the grains available must be fed to piglets. This is not highlighted in the question stem. If this assumption were relaxed, you cannot be sure about the total amount of piglets (which can be from 1 to 5).

What am I getting wrong?

Thank you very much!

Hi Leuro,

No, we are not assuming that all the available grains must be fed. Look, it has to do with the wording of the question.

"Each piglet in a litter is fed exactly one-half pound of a mixture of oats and barley." - So this means that 1/2 pound is fed to each piglet. So if there are 10 piglets, 5 pounds in total is fed today. This 5 pounds will be a mix of oats and barley perhaps 2 pounds oats and 3 pounds barley or whatever.

(1) Piglet A was fed exactly 1/4 of the oats today
So we have a fixed amount of 5 pounds that was fed today out of which 2 pounds was oats. Piglet A was fed 1/4 of the oats.
There is no question of anything remaining. We don't have that total there is 100 pounds of mix etc. Since everyday 1/2 pound is fed to each piglet, that is the quantity we are talking about.

I hope this helps.
_________________

Karishma
Veritas Prep GMAT Instructor

Intern
Joined: 27 Nov 2015
Posts: 47
Re: Each piglet in a litter is fed exactly one-half pound of a mixture of  [#permalink]

### Show Tags

06 Feb 2019, 23:56
Quote:
The total food mixture was split equally among all the piglets. Number of piglets has to be an integer, say n. Each piglet gets the same amount of food i.e. 1/n of the total food. But each piglet also gets less than ¼ of total food and more than 1/6 of total food. The only integral value for n such that 1/6 < 1/n < ¼ is 5.

Hi VeritasKarishma, I did not understand this bit, can you kindly elaborate on this part please?
Re: Each piglet in a litter is fed exactly one-half pound of a mixture of   [#permalink] 06 Feb 2019, 23:56

Go to page   Previous    1   2   [ 26 posts ]

Display posts from previous: Sort by