Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 39719

A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
25 Jun 2012, 02:28
Question Stats:
62% (02:24) correct
38% (01:42) wrong based on 1510 sessions
HideShow timer Statistics



Math Expert
Joined: 02 Sep 2009
Posts: 39719

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
25 Jun 2012, 02:28
6
This post received KUDOS
Expert's post
6
This post was BOOKMARKED
SOLUTIONA marketing firm determined that, of 200 households surveyed, 80 used neither Brand A nor Brand B soap, 60 used only Brand A soap, and for every household that used both brands of soap, 3 used only Brand B soap. How many of the 200 households surveyed used both brands of soap?(A) 15 (B) 20 (C) 30 (D) 40 (E) 45 Given: Attachment:
A marketing firm determined.JPG [ 12.11 KiB  Viewed 17808 times ]
"For every household that used both brands of soap, 3 used only Brand B soap" means that if x used both A and B, then 3x used only B (but not A). So, \(4x+140=200\) > \(x=15\). Answer: A.
_________________
New to the Math Forum? Please read this: All You Need for Quant  PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book  Triangles  Polygons  Coordinate Geometry  Factorials  Circles  Number Theory  Remainders; 8. Overlapping Sets  PDF of Math Book; 10. Remainders  GMAT Prep Software Analysis  SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS)  Tricky questions from previous years.
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? Extrahard Quant Tests with Brilliant Analytics



Manager
Joined: 07 Jun 2011
Posts: 73

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
25 Jun 2012, 05:04
2
This post received KUDOS
60(number of brand A) + X(number of households that use both brans)+ 3x(number of households that use only brand B) + 80 = 200
X = 15



Intern
Joined: 14 Apr 2012
Posts: 13
Location: India
Concentration: Technology, General Management
GMAT Date: 09122012
GPA: 3.5
WE: Information Technology (Retail)

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
26 Jun 2012, 09:52
1
This post was BOOKMARKED
Shouldn't the answer be [C]
60(Brand A) +3x(Brand B)x(Both Brands) = 20080(total is 120 since 80 use neither)
60+2x = 120 => x =30



Manager
Joined: 02 Jun 2011
Posts: 156

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
26 Jun 2012, 14:17
answer  15 (A) did with table for overlapping set.



Intern
Joined: 03 Feb 2012
Posts: 9

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
26 Jun 2012, 16:50
Ans: A (15)
Using given information, 60 people used Brand B. x used both A & B, 3x used only B. Solve for x. x+3x = 60 x=15



Current Student
Joined: 08 Jan 2009
Posts: 326

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
28 Jun 2012, 02:26
3
This post received KUDOS
I think a (poorly drawn) diagram really helps. 60 + x + 3x + 80 = 200 4x = 60 x = 15



Intern
Joined: 22 Jun 2012
Posts: 13
Location: India
GPA: 3.09

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
28 Jun 2012, 02:41
1
This post received KUDOS
1
This post was BOOKMARKED
pallavisatsangi wrote: Shouldn't the answer be [C]
60(Brand A) +3x(Brand B)x(Both Brands) = 20080(total is 120 since 80 use neither)
60+2x = 120 => x =30 No pallavisatsangi The answer is A (15) you can not subtract x (both using A and B) Because in the question it is mentioned that 60 people is only brand A and accordingly 3x people use only Brand B.... if the term 'ONLY' had not been used in the question then you would have subtracted x .. but since in both cases term 'only' has been used, you can not subtract x So eq. becomes 60 +x+3x+80=200 x=15
_________________
\sqrt{[square_root][square_root][square_root][square_root][square_root]}[/square_root][/square_root][/square_root][/square_root][/square_root]????????



Senior Manager
Joined: 06 Aug 2011
Posts: 400

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
28 Jun 2012, 12:22
Bunuel.. plz disclose the ASAP ..because sometimes we cant remember where we have replied.. I think its answer is 30.. OA????
_________________
Bole So Nehal.. Sat Siri Akal.. Waheguru ji help me to get 700+ score !



Math Expert
Joined: 02 Sep 2009
Posts: 39719

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
29 Jun 2012, 02:13
SOLUTIONA marketing firm determined that, of 200 households surveyed, 80 used neither Brand A nor Brand B soap, 60 used only Brand A soap, and for every household that used both brands of soap, 3 used only Brand B soap. How many of the 200 households surveyed used both brands of soap?(A) 15 (B) 20 (C) 30 (D) 40 (E) 45 Given: Attachment:
A marketing firm determined.JPG [ 12.11 KiB  Viewed 17751 times ]
"For every household that used both brands of soap, 3 used only Brand B soap" means that if x used both A and B, then 3x used only B (but not A). So, \(4x+140=200\) > \(x=15\). Answer: A.
_________________
New to the Math Forum? Please read this: All You Need for Quant  PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book  Triangles  Polygons  Coordinate Geometry  Factorials  Circles  Number Theory  Remainders; 8. Overlapping Sets  PDF of Math Book; 10. Remainders  GMAT Prep Software Analysis  SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS)  Tricky questions from previous years.
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? Extrahard Quant Tests with Brilliant Analytics



Intern
Joined: 14 Apr 2012
Posts: 13
Location: India
Concentration: Technology, General Management
GMAT Date: 09122012
GPA: 3.5
WE: Information Technology (Retail)

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
30 Jun 2012, 21:00
Thank q so much Manimani & Bunnel for clarifying my doubt



Manager
Joined: 23 Aug 2011
Posts: 81

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
13 Aug 2012, 07:02
2
This post received KUDOS
Nice question, i took around 1 minute to comprehend this line "for every household that used both brands of soap, 3 used only Brand B soap" and still over looked the word "only" Brand B. I chose (C)30 , but it should be 15. Nice explanation every one. One important thing i observed in these questions, in which we have to deal with Only A/ Only B type issues that it is better to go with VennDia. rather than table as it adds to complexity (only A>not B)and consumes more time than former. On the other hand, the table is easier to work with when the questions deal with "both/neithernor" elements, range of elements. Just my opinion.
_________________
Whatever one does in life is a repetition of what one has done several times in one's life! If my post was worth it, then i deserve kudos



Intern
Joined: 01 Jun 2012
Posts: 21
Location: United States
Concentration: Nonprofit
GPA: 3.83

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
04 Sep 2012, 18:11
A marketing firm determined that, of 200 households surveyed, 80 used neither Brand A nor Brand B soap, 60 used only Brand A soap, and for every household that used both brands of soap, 3 used only Brand B soap. How many of the 200 households surveyed used both brands of soap? A) 15 B) 20 C) 30 D) 40 E) 45 If someone could tell me how to solve the problem using the manhattan method (with grids), that would be awesome. For such a simple problem, I can't figure out how I'm messing up setting up the grid.
Attachments
chart.JPG [ 3.66 MiB  Viewed 16864 times ]



Director
Joined: 22 Mar 2011
Posts: 612
WE: Science (Education)

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
05 Sep 2012, 00:24
egiles wrote: A marketing firm determined that, of 200 households surveyed, 80 used neither Brand A nor Brand B soap, 60 used only Brand A soap, and for every household that used both brands of soap, 3 used only Brand B soap. How many of the 200 households surveyed used both brands of soap?
A) 15 B) 20 C) 30 D) 40 E) 45
If someone could tell me how to solve the problem using the manhattan method (with grids), that would be awesome. For such a simple problem, I can't figure out how I'm messing up setting up the grid. The data in your table should be as follow: x 3x 60 60 80 140 60+x 80+3x 200 From the first line, x + 3x = 60 (the same equation can be obtained using the last line  60 + x + 80 + 3x = 200). Your mistake was misplacing 60  it is the number of households using only brand A (meaning A but not B).
_________________
PhD in Applied Mathematics Love GMAT Quant questions and running.



Math Expert
Joined: 02 Sep 2009
Posts: 39719

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
05 Sep 2012, 00:29
egiles wrote: A marketing firm determined that, of 200 households surveyed, 80 used neither Brand A nor Brand B soap, 60 used only Brand A soap, and for every household that used both brands of soap, 3 used only Brand B soap. How many of the 200 households surveyed used both brands of soap?
A) 15 B) 20 C) 30 D) 40 E) 45
If someone could tell me how to solve the problem using the manhattan method (with grids), that would be awesome. For such a simple problem, I can't figure out how I'm messing up setting up the grid. Merging similar topics. Please search the forum before posting a question.
_________________
New to the Math Forum? Please read this: All You Need for Quant  PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book  Triangles  Polygons  Coordinate Geometry  Factorials  Circles  Number Theory  Remainders; 8. Overlapping Sets  PDF of Math Book; 10. Remainders  GMAT Prep Software Analysis  SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS)  Tricky questions from previous years.
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? Extrahard Quant Tests with Brilliant Analytics



Manager
Joined: 26 Jul 2011
Posts: 117
Location: India
WE: Marketing (Manufacturing)

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
06 Sep 2012, 05:50
Answer is 15...I have sticky memory (I don't know if its good or bad). I am afraid, but unknowingly I have memorized lot of solutions and I tend to use that memory on mocks (As most of the problems in the post come from prep and Manhattan tests). The bad thing is when I am posed with a problem, perhaps testing the same concept, I just take too much of a time..should I keep doing problems from the posts or should I practice from some other source? Guys need your advice on this...



Intern
Joined: 25 Jun 2012
Posts: 36

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
10 Dec 2012, 16:23
fun question!
these always remind me of sudoku.
in any case, the twist here is that the relationship defining the square's occupant is a bit different than just concrete numbers, it's a tiny little ratio problem stuck inside of an overlapping set problem.
1:3 = 60
unknown multiplier of x...and: 1x+3x= 60 ... 4x= 60 ... x=15.



Intern
Joined: 07 Oct 2012
Posts: 4

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
30 Jan 2013, 11:11
Hi, I have a question/answer from the OG book that I don't understand, if someone could help me it could be really cool: A marketing firm determined that, of 200 households surveyed, 80 used neither brand A nor Brand B soap, 60 used only Brand A soap, and for every household that used both brand of soap, 3 use only Brand B soap. How many of the 200 households surveyed used both brands of soap? 60+x+3x=120 x=15
I don't understand from where does the 3x come from... Thanks a lot Best regard



Math Expert
Joined: 02 Sep 2009
Posts: 39719

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
30 Jan 2013, 11:16
sokoma wrote: Hi, I have a question/answer from the OG book that I don't understand, if someone could help me it could be really cool: A marketing firm determined that, of 200 households surveyed, 80 used neither brand A nor Brand B soap, 60 used only Brand A soap, and for every household that used both brand of soap, 3 use only Brand B soap.
How many of the 200 households surveyed used both brands of soap?60+x+3x=120 x=15
I don't understand from where does the 3x come from... Thanks a lot Best regard Merging similar topics. Please refer to the solutions above. P.S. Please read carefully and follow: rulesforpostingpleasereadthisbeforeposting133935.html Pay attention to the rules #1, 3, 5, 7, and 8!
_________________
New to the Math Forum? Please read this: All You Need for Quant  PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book  Triangles  Polygons  Coordinate Geometry  Factorials  Circles  Number Theory  Remainders; 8. Overlapping Sets  PDF of Math Book; 10. Remainders  GMAT Prep Software Analysis  SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS)  Tricky questions from previous years.
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? Extrahard Quant Tests with Brilliant Analytics



Intern
Joined: 09 Jan 2014
Posts: 3

Re: A marketing firm determined that, of 200 households surveyed [#permalink]
Show Tags
09 Jan 2014, 09:49
Thanks a lot to everybody for your explainations... I still have issues with understanding the exercise. Indeed, when we just said that "for every household that used both brands of soap, 3 used only Brand B soap" what did we mean exactly? It is a bit confusing for me... First we say that they use both brands, but then we say that 3 (3 from what?) use only B... And all the 4x and 1x thing is also confusing me




Re: A marketing firm determined that, of 200 households surveyed
[#permalink]
09 Jan 2014, 09:49



Go to page
1 2
Next
[ 29 posts ]




