Author 
Message 
TAGS:

Hide Tags

Intern
Joined: 13 Jun 2005
Posts: 17

A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
27 Jun 2007, 16:26
Question Stats:
70% (03:12) correct 30% (03:24) wrong based on 728 sessions
HideShow timer Statistics
A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? (A) 10 (B) 20 (C) 30 (D) 32 (E) 34
Official Answer and Stats are available only to registered users. Register/ Login.




Math Expert
Joined: 02 Sep 2009
Posts: 64947

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
27 Sep 2014, 12:31
shreygupta3192 wrote: A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? (A) 10 (B) 20 (C) 30 (D) 32 (E) 34 hey can any1 plz tell me .. if ques says that no 20 ounce bottles are sold.. then y r we considering "20*12" while calculating the new ratio.. wats the meaning and the use of that line above.." no 20 ounce bottles are sold" y can`t we directly put 0 bottles for 20 ounces.. y can`t we go directly for .. 25=(20(0)+40(x))/x.. confused.. No. The question asks about the average weight of bottles which are not sold. A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? (A) 10 (B) 20 (C) 30 (D) 32 (E) 34 The current average of 20 (35  15) and 40ounce (40  5) bottles is 35, thus there must be 3 times as many 40ounce bottles as 20ounce bottles. Since there are total of 48 bottles, then there must be 12 20ounce bottles and 36 40ounce bottles. Now, we need to sell ONLY 40ounce bottles so that the average to become 25. Same way, 25 is 5 away from 20 and 15 away from 40, so after selling some number of 40ounce bottles, there must be 3 times as many 20ounce bottles as 40ounce bottles. So, there must be 12 20ounce bottles and 12/3 = 4 40ounce bottles. Therefore, 36  4 = 32 40ounce bottles must be sold. Answer: D. Hope it's clear.
_________________




Manager
Joined: 21 Jun 2006
Posts: 206

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
27 Jun 2007, 20:51
32
Here is how I got it:
Average is 35 ounces
x is # of 20 ounce bottles
y is # of 40 ounce bottles
20x+40y/x+y = 35
solve to get y=3x
x+y=48 bottles
x=12, y=36
20x+40z/x+z=25
plug x=12 and solve for z, we get z = 4
So, yz is # of bottles sold i.e 364 = 32




Director
Joined: 26 Feb 2006
Posts: 605

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
27 Jun 2007, 16:55
dred wrote: A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? 10 20 30 32 34
D.
20 p + 40 (1p) = 35
p = 1/4
so 20 oz = 12
12 x 20 / (12+x) + 40x / (12+x) = 25
x = 4
so 32 bottles with 40 oz should be sold.



Manager
Joined: 26 Jun 2007
Posts: 74

A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
Updated on: 27 Sep 2014, 11:47
A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold?
(A) 10 (B) 20 (C) 30 (D) 32 (E) 34
Originally posted by GGUY on 22 Jan 2008, 01:09.
Last edited by Bunuel on 27 Sep 2014, 11:47, edited 1 time in total.
Renamed the topic, edited the question, added the OA and moved to PS forum.



VP
Joined: 04 May 2006
Posts: 1130
Schools: CBS, Kellogg

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
22 Jan 2008, 01:34
GGUY wrote: Taken From MGMAT # 3 A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? (A) 10 (B) 20 (C) 30 (D) 32 (E) 34 Please Explain D 20x + 40y = 35*48 20x + 40 (yt) = 25*(48t) 20x + 40y 40t = 25*48  25t 35*48 40t = 25*48 25t t =32
_________________



Manager
Joined: 26 Jun 2007
Posts: 74

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
22 Jan 2008, 12:10
sondenso wrote: GGUY wrote: Taken From MGMAT # 3 A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? (A) 10 (B) 20 (C) 30 (D) 32 (E) 34 Please Explain D 20x + 40y = 35*48 20x + 40 (yt) = 25*(48t) 20x + 40y 40t = 25*48  25t 35*48 40t = 25*48 25t t =32 Nice, OA= D. My approach was to find how many bottles of 40 need to remain in order to have 25 Av: (1) 12*20+40*t = 25* (t+12) (2) t=4 (3) we found 12 bt of 20 ounce and 36 of 40 ounce so 364=32 any more takers?



Intern
Joined: 08 Dec 2013
Posts: 29

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
27 Sep 2014, 09:27
hey can any1 plz tell me .. if ques says that no 20 ounce bottles are sold.. then y r we considering "20*12" while calculating the new ratio.. wats the meaning and the use of that line above.." no 20 ounce bottles are sold" y can`t we directly put 0 bottles for 20 ounces.. y can`t we go directly for .. 25=(20(0)+40(x))/x.. confused..



Intern
Joined: 08 Dec 2013
Posts: 29

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
27 Sep 2014, 18:02
hi thanx for ur valuable answer but i`ll be glad if u could put it algebrically...that will be more easier for me to understand.
also, plz tell me wat is the point of "20 ounces bottles not sold" ... y r we still considering that while calculating the new ratio..it should be 0 ..huh..



Math Expert
Joined: 02 Sep 2009
Posts: 64947

A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
29 Sep 2014, 05:12
shreygupta3192 wrote: hi thanx for ur valuable answer but i`ll be glad if u could put it algebrically...that will be more easier for me to understand.
also, plz tell me wat is the point of "20 ounces bottles not sold" ... y r we still considering that while calculating the new ratio..it should be 0 ..huh.. Algebraic ways are given in posts above. As for your other question. I think you misunderstood the problem. There are 12 20ounce and 36 40ounce bottles. The average volume of those 48 bottles is 35 ounces. We need to find how many of 36 40ounce bottles must be sold for the average volume of the remaining bottles to be reduced to 25 ounces.
_________________



Manager
Joined: 24 Jun 2014
Posts: 51
Concentration: Social Entrepreneurship, Nonprofit

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
07 Mar 2015, 23:03
shreygupta3192 wrote: hi thanx for ur valuable answer but i`ll be glad if u could put it algebrically...that will be more easier for me to understand.
also, plz tell me wat is the point of "20 ounces bottles not sold" ... y r we still considering that while calculating the new ratio..it should be 0 ..huh.. Shrey, We can establish from question here x is number of 20 ounce bottles , y is 40 ounce bottles x+y=48 20x+40y=1680 x=12,y=36 Coming to remaining part of question Value of 20 ounce bottles will be 0 , if we consider the bottles sold. 20x+40z=25(x+z); z = remaining bottles x=12 , no removal here 20*12+40(z)=25(12+z);z=4 if remaining is 4 ,then 364 were sold=32. However Brunel's approach is good time saving approach.



Intern
Joined: 12 Oct 2014
Posts: 44
Location: India
Concentration: Finance, General Management
WE: Analyst (Investment Banking)

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
09 Mar 2015, 19:47
Bunuel wrote: shreygupta3192 wrote: A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? (A) 10 (B) 20 (C) 30 (D) 32 (E) 34 hey can any1 plz tell me .. if ques says that no 20 ounce bottles are sold.. then y r we considering "20*12" while calculating the new ratio.. wats the meaning and the use of that line above.." no 20 ounce bottles are sold" y can`t we directly put 0 bottles for 20 ounces.. y can`t we go directly for .. 25=(20(0)+40(x))/x.. confused.. No. The question asks about the average weight of bottles which are not sold. A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? (A) 10 (B) 20 (C) 30 (D) 32 (E) 34 The current average of 20 (35  15) and 40ounce (40  5) bottles is 35, thus there must be 3 times as many 40ounce bottles as 20ounce bottles. Since there are total of 48 bottles, then there must be 12 20ounce bottles and 36 40ounce bottles. Now, we need to sell ONLY 40ounce bottles so that the average to become 25. Same way, 25 is 5 away from 20 and 15 away from 40, so after selling some number of 40ounce bottles, there must be 3 times as many 20ounce bottles as 40ounce bottles. So, there must be 12 20ounce bottles and 12/3 = 4 40ounce bottles. Therefore, 36  4 = 32 40ounce bottles must be sold. Answer: D. Hope it's clear. Fantastic solution Bunuel, you are a legend !!



Intern
Joined: 20 Aug 2014
Posts: 7
Location: United States
GPA: 3.27

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
29 May 2015, 06:55
[48(35)x(40) ] / (48x) = 25
48(35)  x(40) = 48(25)  x(25)
48(10) = x(15)
48(2/3) = x
32= x



Intern
Joined: 18 Mar 2015
Posts: 21
Location: India
Concentration: Technology, Entrepreneurship
GPA: 4
WE: Engineering (Computer Software)

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
29 May 2015, 08:49
Quote: A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? A.10 B.20 C.30 D.32 E.34
Let there be x 20 ounces bottles and y 40 ounces bottles. Now, x + y = 48 (Given) Given average volume of all 48 bottles is 35 ounces. ==> (20*x+ 40*y)/48 = 35 ==> (20*x+ 40*y) = 35 * 48 (1) Now let us assume k 40 ounces bottles are sold and then average volume of (48k) bottles is 25. ==> (20*x+ 40*[yk])/(48k) = 25 ==> (20*x+ 40*y  40*k) = 25* (48  k) ==> (35 * 48)  40*k = 25*48  25*k ==> 15*k = 480 ==> k = 32. Hence D.



Manager
Status: folding sleeves up
Joined: 26 Apr 2013
Posts: 120
Location: India
Concentration: Finance, Strategy
GMAT 1: 530 Q39 V23 GMAT 2: 560 Q42 V26
GPA: 3.5
WE: Consulting (Computer Hardware)

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
08 Jul 2015, 18:53
dred wrote: A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? 10 20 30 32 34 You can also resolve this question with weighted avg formula 20 40 \ / 35 / \ 15 5 Ratio : 3: 1 or we can say that 40 ounce bottles are three time as many as 20 ounce so number of 40 ounce bottles are 36 and 20 ounce bottles are 12 next (20(12)+ 40x)/12+x = 25 >where x is the remaining 40 ounce bottles x= 4 i.e. 364=> 32 of 40 ounce bottles have been sold



Manager
Status: folding sleeves up
Joined: 26 Apr 2013
Posts: 120
Location: India
Concentration: Finance, Strategy
GMAT 1: 530 Q39 V23 GMAT 2: 560 Q42 V26
GPA: 3.5
WE: Consulting (Computer Hardware)

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
07 Apr 2016, 10:55
email2vm wrote: dred wrote: A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold? 10 20 30 32 34 You can also resolve this question with weighted avg formula 20 40 \ / 35 / \ 15 5 Ratio : 3: 1 or we can say that 40 ounce bottles are three time as many as 20 ounce so number of 40 ounce bottles are 36 and 20 ounce bottles are 12 next (20(12)+ 40x)/12+x = 25 >where x is the remaining 40 ounce bottles x= 4 i.e. 364=> 32 of 40 ounce bottles have been sold another solution: Ratio is 3:1 ==>36 bottles of 40 ounces and 12 bottles of 20 ounces again 40 20 \ / 25 / \ 5 15 1:3 36x/12 =1/3 x=32



VP
Joined: 07 Dec 2014
Posts: 1258

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
08 Apr 2016, 12:39
let t=#20 oz bottles let f=#40 oz bottles x=#40 oz bottles that have to be sold equation 1: 20t+40f=(48)(35)=1680 oz equation 2: 20t+40f40x=25(48x) oz subtracting 2 from 1, 40x=480+25x x=32 40 oz bottles have to be sold



Current Student
Joined: 12 Aug 2015
Posts: 2519

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
22 Apr 2016, 17:08
its taking a bit longer to solve using the algebraic approach.. Anyone with any other approach? Regards CC Abhishek009StoneCold
_________________



Math Expert
Joined: 02 Aug 2009
Posts: 8751

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
22 Apr 2016, 20:44
stonecold wrote: its taking a bit longer to solve using the algebraic approach.. Anyone with any other approach? Regards CC Abhishek009StoneCold Hi, the other method would be weighted average method.. people have already used it above, still ill do it once again.. TWO steps.. first  initial numbers20 and 40 avail and average is 35.. so \(\frac{# of 20}{# of 40} = \frac{4035}{3520} = \frac{1}{3}\) so # of 20 \(= \frac{1}{1+3} *48 =12\).. and # of 40 ounces = 4812 = 36 second  20 and 40 avail and average is 25.. so\(\frac{# of 20}{# of 40} = \frac{4025}{2520} =\frac{3}{1}\) so # of 20\(= \frac{3}{1+3} *x =12\), here we know # of 20 ounces remains constant.. so x= 16 and # of 40 ounces = 1612 = 4.. now # of 40 ounces bottle sold = 364 = 32
_________________



VP
Joined: 07 Dec 2014
Posts: 1258

Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
Show Tags
25 Apr 2017, 14:25
dred wrote: A convenience store currently stocks 48 bottles of mineral water. The bottles have two sizes of either 20 or 40 ounces each. The average volume per bottle the store currently has in stock is 35 ounces. How many 40 ounce bottles must be sold for the average volume per bottle to be reduced to 25 ounces if no 20 ounce bottles are sold?
(A) 10 (B) 20 (C) 30 (D) 32 (E) 34 let x=number of 40 ounce bottles to be sold total volume=48*35=1680 ounces (168040x)/(48x)=25 x=32 bottles D




Re: A convenience store currently stocks 48 bottles of mineral water. The
[#permalink]
25 Apr 2017, 14:25



Go to page
1 2
Next
[ 26 posts ]

