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

 It is currently 22 Jul 2018, 11:35

### 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

# A polling company found that, of 300 households surveyed

Author Message
TAGS:

### Hide Tags

Manager
Joined: 24 Jun 2010
Posts: 136
Concentration: Strategy, Technology
A polling company found that, of 300 households surveyed  [#permalink]

### Show Tags

06 Oct 2010, 18:35
2
10
00:00

Difficulty:

45% (medium)

Question Stats:

71% (02:07) correct 29% (02:31) wrong based on 350 sessions

### HideShow timer Statistics

A polling company found that, of 300 households surveyed, 120 spent at least $100 per month on both gasoline and electricity, 60 spent at least$100 per month on gasoline but not on electricity, and for every household that did not spend at least $100 per month on gasoline or electricity, 4 spent at least$100 per month on electricity but not on gasoline. How many of the 300 households did not spend at least $100 per month on either gasoline or electricity? A. 24 B. 30 C. 36 D. 90 E. 96 ##### Most Helpful Community Reply Current Student Joined: 29 Mar 2012 Posts: 317 Location: India GMAT 1: 640 Q50 V26 GMAT 2: 660 Q50 V28 GMAT 3: 730 Q50 V38 Re: Gasoline and Electricity [#permalink] ### Show Tags Updated on: 09 Jul 2012, 01:08 5 Quote: A polling company found that, of 300 households surveyed, 120 spent at least$100 per month on both gasoline and electricity, 60 spent at least $100 per month on gasoline but not on electricity, and for every household that did not spend at least$100 per month on gasoline or electricity, 4 spent at least $100 per month on electricity but not on gasoline. How many of the 300 households did not spend at least$100 per month on either gasoline or electricity?

A. 24
B. 30
C. 36
D. 90
E. 96
Hi,

Please refer to the attached Venn diagram:
Here, x = Number of households neither using electricity nor gasoline.
Now, $$60+120+4x+x=300$$
or x = 24

Regards,
Attachments

Venn.jpg [ 22.47 KiB | Viewed 5068 times ]

Originally posted by cyberjadugar on 20 Jun 2012, 23:06.
Last edited by cyberjadugar on 09 Jul 2012, 01:08, edited 1 time in total.
##### General Discussion
Retired Moderator
Joined: 02 Sep 2010
Posts: 775
Location: London

### Show Tags

07 Oct 2010, 00:52
krazo wrote:
Here is one I thought was pretty good...

A polling company found that, of 300 households surveyed, 120 spent at least $100 per month on both gasoline and electricity, 60 spent at least$100 per month on gasoline but not on electricity, and for every household that did not spend at least $100 per month on gasoline or electricity, 4 spent at least$100 per month on electricity but not on gasoline. How many of the 300 households did not spend at least $100 per month on either gasoline or electricity? (A) 24 (B) 30 (C) 36 (D) 90 (E) 96 120 spend$100 on gas & electricity
60 spend $100 on gas but not on electricity For every one that spent <$100 on both there are 4 that spent $100 on electricity not gas Let the ones that spent on neither be x The ones that spent on just electricity will be 4x Total households = Those who spend >$100 on both + Those who spend >$100 on just one + Those who spend <$100 on both = 120 + 60 + 4x + x

300 = 180 + 5x implies x=24

_________________
Math Expert
Joined: 02 Sep 2009
Posts: 47183
Re: A polling company found that, of 300 households surveyed  [#permalink]

### Show Tags

21 Jun 2012, 01:36
1
1
A polling company found that, of 300 households surveyed, 120 spent at least $100 per month on both gasoline and electricity, 60 spent at least$100 per month on gasoline but not on electricity, and for every household that did not spend at least $100 per month on gasoline or electricity, 4 spent at least$100 per month on electricity but not on gasoline. How many of the 300 households did not spend at least $100 per month on either gasoline or electricity? A. 24 B. 30 C. 36 D. 90 E. 96 {Total} = {Only Gasoline} + {Only Electricity} + {Both} + {Neither}. Notice that this formula is different from {Total} = {Group #1} + {Group #2}} - {Both} + {Neither}; $$300 = 60 + 4x + 120 + x$$ --> $$x=24$$. Answer: A. Hope it's clear. _________________ Director Joined: 27 May 2012 Posts: 513 Re: A polling company found that, of 300 households surveyed [#permalink] ### Show Tags 21 Jun 2012, 04:20 Bunuel wrote: A polling company found that, of 300 households surveyed, 120 spent at least$100 per month on both gasoline and electricity, 60 spent at least $100 per month on gasoline but not on electricity, and for every household that did not spend at least$100 per month on gasoline or electricity, 4 spent at least $100 per month on electricity but not on gasoline. How many of the 300 households did not spend at least$100 per month on either gasoline or electricity?

A. 24
B. 30
C. 36
D. 90
E. 96

{Total} = {Only Gasoline} + {Only Electricity} + {Both} + {Neither}. Notice that this formula is different from {Total} = {Group #1} + {Group #2}} - {Both} + {Neither};

$$300 = 60 + 4x + 120 + x$$ --> $$x=24$$.

Hope it's clear.

I know this is very basic , but a reconfirmation will help

" My confusion was the term " OR "

A OR B means AUB ( Total ) right so in this case E OR G means EUG( Total )

so EUG = only E + Only G + Both + Neither ( This one we are using )
also EUG = Group E + group G - both + Neither ( This one we are not using here )

Please let me now if anything that I have written in Blue is wrong !!

I want to understand if A or B = AUB = Total ??
_________________

- Stne

Math Expert
Joined: 02 Sep 2009
Posts: 47183
Re: A polling company found that, of 300 households surveyed  [#permalink]

### Show Tags

21 Jun 2012, 04:51
stne wrote:
Bunuel wrote:
A polling company found that, of 300 households surveyed, 120 spent at least $100 per month on both gasoline and electricity, 60 spent at least$100 per month on gasoline but not on electricity, and for every household that did not spend at least $100 per month on gasoline or electricity, 4 spent at least$100 per month on electricity but not on gasoline. How many of the 300 households did not spend at least $100 per month on either gasoline or electricity? A. 24 B. 30 C. 36 D. 90 E. 96 {Total} = {Only Gasoline} + {Only Electricity} + {Both} + {Neither}. Notice that this formula is different from {Total} = {Group #1} + {Group #2}} - {Both} + {Neither}; $$300 = 60 + 4x + 120 + x$$ --> $$x=24$$. Answer: A. Hope it's clear. I know this is very basic , but a reconfirmation will help " My confusion was the term " OR " A OR B means AUB ( Total ) right so in this case E OR G means EUG( Total ) so EUG = only E + Only G + Both + Neither ( This one we are using ) also EUG = Group E + group G - both + Neither ( This one we are not using here ) Please let me now if anything that I have written in Blue is wrong !! I want to understand if A or B = AUB = Total ?? Two formulas are: {Total} = {Group #1} + {Group #2} - {Both} + {Neither} {Total} = {Only Group #1} + {Only Group #2} + {Both} + {Neither} Now, if we are told that there are 10 people in {Group #1} and 15 people in {Group #2}, then the number of people in {Group #1} OR in {Group #2} can be expressed as {Group #1} + {Group #2} - {Both}. But to get the total number of people you should add to that the number of people who are in neither of groups. Hope it's clear. _________________ Manager Status: Never ever give up on yourself.Period. Joined: 23 Aug 2012 Posts: 147 Location: India Concentration: Finance, Human Resources GMAT 1: 570 Q47 V21 GMAT 2: 690 Q50 V33 GPA: 3.5 WE: Information Technology (Investment Banking) Re: A polling company found that, of 300 households surveyed [#permalink] ### Show Tags 17 Sep 2012, 06:25 2 Different approach: I think if there are two overlapping sets then quick way to solve the problem is to form a chart rather than to draw a Venn diagram..here's the solution for above problem in chart way.. --------------Electricity----Non-Electricity--Total Gasoline------120-----------60--------------180 Non-Gasln-----4x-------------x--------------120 Total -------------------------------------------300 now 4x + x =120, so 5x=120 and hence x=24. _________________ Don't give up on yourself ever. Period. Beat it, no one wants to be defeated (My journey from 570 to 690) : http://gmatclub.com/forum/beat-it-no-one-wants-to-be-defeated-journey-570-to-149968.html Manager Joined: 10 Mar 2014 Posts: 212 Re: A polling company found that, of 300 households surveyed [#permalink] ### Show Tags 07 Aug 2014, 12:06 Bunuel wrote: A polling company found that, of 300 households surveyed, 120 spent at least$100 per month on both gasoline and electricity, 60 spent at least $100 per month on gasoline but not on electricity, and for every household that did not spend at least$100 per month on gasoline or electricity, 4 spent at least $100 per month on electricity but not on gasoline. How many of the 300 households did not spend at least$100 per month on either gasoline or electricity?

A. 24
B. 30
C. 36
D. 90
E. 96

{Total} = {Only Gasoline} + {Only Electricity} + {Both} + {Neither}. Notice that this formula is different from {Total} = {Group #1} + {Group #2}} - {Both} + {Neither};

$$300 = 60 + 4x + 120 + x$$ --> $$x=24$$.

Hope it's clear.

HI Bunuel,

I know its a silly question but i didn't understand how you took 4x from question stem.

Thanks.
SVP
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1837
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
A polling company found that, of 300 households surveyed  [#permalink]

### Show Tags

08 Aug 2014, 00:19
PathFinder007 wrote:
Bunuel wrote:
A polling company found that, of 300 households surveyed, 120 spent at least $100 per month on both gasoline and electricity, 60 spent at least$100 per month on gasoline but not on electricity, and for every household that did not spend at least $100 per month on gasoline or electricity, 4 spent at least$100 per month on electricity but not on gasoline. How many of the 300 households did not spend at least $100 per month on either gasoline or electricity? A. 24 B. 30 C. 36 D. 90 E. 96 {Total} = {Only Gasoline} + {Only Electricity} + {Both} + {Neither}. Notice that this formula is different from {Total} = {Group #1} + {Group #2}} - {Both} + {Neither}; $$300 = 60 + 4x + 120 + x$$ --> $$x=24$$. Answer: A. Hope it's clear. HI Bunuel, I know its a silly question but i didn't understand how you took 4x from question stem. Please clarify. Thanks. Not Bunuel, but lets try The answer lies in the highlighted part of the question Only Electricity is 4 times of (No Gas No electricity) So, if "x" = No Gas No electricity, then 4x = Only electricity Please refer the Venn diagram above; it explains perfect In this problem, the term "atleast 100" is the confusion creator which is repeated 5 times; although "100" is not required for any calculation. May be GMAT trick _________________ Kindly press "+1 Kudos" to appreciate Target Test Prep Representative Status: Head GMAT Instructor Affiliations: Target Test Prep Joined: 04 Mar 2011 Posts: 2679 Re: A polling company found that, of 300 households surveyed [#permalink] ### Show Tags 14 Nov 2017, 07:20 1 krazo wrote: A polling company found that, of 300 households surveyed, 120 spent at least$100 per month on both gasoline and electricity, 60 spent at least $100 per month on gasoline but not on electricity, and for every household that did not spend at least$100 per month on gasoline or electricity, 4 spent at least $100 per month on electricity but not on gasoline. How many of the 300 households did not spend at least$100 per month on either gasoline or electricity?

A. 24
B. 30
C. 36
D. 90
E. 96

We can create the following equation:

Total = number who spent at least 100 on gasoline only + number who spent at least 100 on electricity only + number who spend at least 100 on both + number who spent at least 100 on neither

If we let x = number who spent at least 100 on neither, then 4x = number who spent at least 100 on electricity only, and we have:

300 = 60 + 4x + 120 + x

300 = 180 + 5x

120 = 5x

x = 24

_________________

Jeffery Miller

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Senior Manager
Status: love the club...
Joined: 24 Mar 2015
Posts: 278
Re: A polling company found that, of 300 households surveyed  [#permalink]

### Show Tags

23 Nov 2017, 16:32
krazo wrote:
A polling company found that, of 300 households surveyed, 120 spent at least $100 per month on both gasoline and electricity, 60 spent at least$100 per month on gasoline but not on electricity, and for every household that did not spend at least $100 per month on gasoline or electricity, 4 spent at least$100 per month on electricity but not on gasoline. How many of the 300 households did not spend at least \$100 per month on either gasoline or electricity?

A. 24
B. 30
C. 36
D. 90
E. 96

a ratio between "none and only electricity" is given

so, none and only electricity = (300 - 120 -60) = 120

now, according to the ratio
120 * 1/5 = 24

thanks
Re: A polling company found that, of 300 households surveyed &nbs [#permalink] 23 Nov 2017, 16:32
Display posts from previous: Sort by

# Events & Promotions

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne 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®.