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

It is currently 18 Nov 2018, 19:36

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel
Events & Promotions in November
PrevNext
SuMoTuWeThFrSa
28293031123
45678910
11121314151617
18192021222324
2526272829301
Open Detailed Calendar
  • How to QUICKLY Solve GMAT Questions - GMAT Club Chat

     November 20, 2018

     November 20, 2018

     09:00 AM PST

     10:00 AM PST

    The reward for signing up with the registration form and attending the chat is: 6 free examPAL quizzes to practice your new skills after the chat.
  • The winning strategy for 700+ on the GMAT

     November 20, 2018

     November 20, 2018

     06:00 PM EST

     07:00 PM EST

    What people who reach the high 700's do differently? We're going to share insights, tips and strategies from data we collected on over 50,000 students who used examPAL.

X percents of the rooms are suits, Y percent of the rooms

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Director
Director
User avatar
Joined: 26 Feb 2006
Posts: 865
X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 17 Oct 2007, 22:24
9
27
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

62% (02:08) correct 38% (02:21) wrong based on 538 sessions

HideShow timer Statistics

X percents of the rooms are suits, Y percent of the rooms are painted light blue. Which of the following best represents the least percentage of the light blue painted suits?

A. X-Y
B. Y-X +100
C. 100X-Y
D. X+Y-100
E. 100-XY
Director
Director
User avatar
Joined: 20 Aug 2007
Posts: 850
Location: Chicago
Schools: Chicago Booth 2011
  [#permalink]

Show Tags

New post 18 Oct 2007, 09:50
Isn't this just a union/venn diagram?
If we let LS = light blue suites we get

x + y - LS is less than or equal to 100, so
LS >= x + y - 100

Now let's try x = 50% and y = 50%, there's no guarantee that there is an overlap. If we plug in we get B >= 0
But if we try x = 75%, y = 75%, there is bound to be overlap and we get B >= 50% (50% or more rooms are guaranteed to be light blue suites).
Not sure though.
Manager
Manager
avatar
Joined: 07 Nov 2009
Posts: 247
Pained rooms  [#permalink]

Show Tags

New post 05 Jul 2010, 23:11
2
1
123. X percents of the rooms are suits, Y percent of the rooms are painted
light blue. Which of the following best represents the least percentage of
the light blue painted suits?
1) X-Y
2)Y-X +100
3)100X-Y
4)X+Y-100
e)100-XY

Please explain your method. Also please help me know in case the questions was as below then how we can solve that:
123. X percents of the rooms are suits, Y percent of the rooms are painted
light blue. Which of the following best represents the MAX percentage of
the light blue painted suits?
Senior Manager
Senior Manager
avatar
Joined: 25 Jun 2009
Posts: 279
Re: Pained rooms  [#permalink]

Show Tags

New post 06 Jul 2010, 02:46
1
rohitgoel15 wrote:
123. X percents of the rooms are suits, Y percent of the rooms are painted
light blue. Which of the following best represents the least percentage of
the light blue painted suits?
1) X-Y
2)Y-X +100
3)100X-Y
4)X+Y-100
e)100-XY

Please explain your method. Also please help me know in case the questions was as below then how we can solve that:
123. X percents of the rooms are suits, Y percent of the rooms are painted
light blue. Which of the following best represents the MAX percentage of
the light blue painted suits?



Answer is going to be the same whether its MAX or MIN percentage.

Using the simple formula

100 = X + Y - BOTH - > Here X = % of Suits , Y = % of light blue painted rooms and BOTH = % of suits painted in light blue colour

So now, BOTH = X+Y -100 and now you can manipulate the value of X and Y to get the max and minimum values.

Hence Answer D

Hope this helps.
Intern
Intern
avatar
Joined: 24 Apr 2014
Posts: 9
Re:  [#permalink]

Show Tags

New post 25 Apr 2014, 20:25
2
1
sonibubu wrote:
Isn't this just a union/venn diagram?
If we let LS = light blue suites we get

x + y - LS is less than or equal to 100, so
LS >= x + y - 100

Now let's try x = 50% and y = 50%, there's no guarantee that there is an overlap. If we plug in we get B >= 0
But if we try x = 75%, y = 75%, there is bound to be overlap and we get B >= 50% (50% or more rooms are guaranteed to be light blue suites).
Not sure though.


I agree with you:
% suited + %light - % suited and light + % no suited or light = 100 %
Because % of no suited or light >= 0
==> x + y - % suited light <= 100
--> % suited & light >= x + y - 100
--> min SL = x+y - 100 :D
Manager
Manager
avatar
B
Joined: 10 Mar 2014
Posts: 198
Premium Member
Re: X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 16 Jul 2014, 03:16
Hi Bunuel,

Although I got the right answer. Could you please provide your comments on this.

I did it in a following way

Lets total are 100 rooms. so x%of 100 = x.
and Y %of 100 = y

100 = x+y-both +neither

both = x+y-100. Assuming neither = 0


I am not sure this is the right way.

Please provide your comments on this

Thanks
Manager
Manager
avatar
Joined: 25 Apr 2014
Posts: 113
X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 17 Jul 2014, 14:56
Hi Bunuel / Experts

Can you please explain me the question with the help of 2-D matrix. I am terribly stuck :cry:
SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1826
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 17 Jul 2014, 19:28
2
maggie27 wrote:
Hi Bunuel / Experts

Can you please explain me the question with the help of 2-D matrix. I am terribly stuck :cry:


Not an expert, but lets try :)

Refer Diagram below:

To maximize the value "a" (Overlap), 100-(x+y) should be zero

100 = x-a + y-a + a + 100 - (x+y)

100 = x+y-a

a = x+ y - 100

Answer = D
Attachments

overl.png
overl.png [ 6.97 KiB | Viewed 5977 times ]


_________________

Kindly press "+1 Kudos" to appreciate :)

SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1826
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 17 Jul 2014, 19:31
Himalayan wrote:
X percents of the rooms are suits, Y percent of the rooms are painted light blue. Which of the followingbest represents the least percentage of the light blue painted suits?

A. X-Y
B. Y-X +100
C. 100X-Y
D. X+Y-100
E. 100-XY


Bunuel, looking at the answer, I doubt the highlighted portion of the wording.

Any comments please? :)
_________________

Kindly press "+1 Kudos" to appreciate :)

Manager
Manager
avatar
Joined: 25 Apr 2014
Posts: 113
Re: X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 17 Jul 2014, 19:57
PareshGmat wrote:
maggie27 wrote:
Hi Bunuel / Experts

Can you please explain me the question with the help of 2-D matrix. I am terribly stuck :cry:


Not an expert, but lets try :)

Refer Diagram below:

To maximize the value "a" (Overlap), 100-(x+y) should be zero

100 = x-a + y-a + a + 100 - (x+y)

100 = x+y-a

a = x+ y - 100

Answer = D



Hahahaha... if not an expert den "expert in making" for sure :-D
Thanks for the explanation .However, I was stuck with 2-D matrix for it, with which I started fixing it.
Can u please help me understand the same with the matrix too... :o
SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1826
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 17 Jul 2014, 21:42
2
maggie27 wrote:
PareshGmat wrote:
maggie27 wrote:
Hi Bunuel / Experts

Can you please explain me the question with the help of 2-D matrix. I am terribly stuck :cry:


Not an expert, but lets try :)

Refer Diagram below:

To maximize the value "a" (Overlap), 100-(x+y) should be zero

100 = x-a + y-a + a + 100 - (x+y)

100 = x+y-a

a = x+ y - 100

Answer = D



Hahahaha... if not an expert den "expert in making" for sure :-D
Thanks for the explanation .However, I was stuck with 2-D matrix for it, with which I started fixing it.
Can u please help me understand the same with the matrix too... :o



Please have a look below:
Attachments

ma.png
ma.png [ 6.18 KiB | Viewed 5973 times ]


_________________

Kindly press "+1 Kudos" to appreciate :)

Manager
Manager
avatar
Joined: 30 Mar 2013
Posts: 109
GMAT ToolKit User
Re: X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 09 Nov 2014, 11:01
I too did it with the simple formula. But even within set sets have max/ min overlaps. I'm not sure how to apply that to this question though
Manager
Manager
avatar
B
Status: Manager to Damager!
Affiliations: MBA
Joined: 22 May 2014
Posts: 68
Location: United States
Schools: Insead July'17
Re: X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 11 May 2016, 07:23
Hi..
Can anyone help me to understand my doubt?
What if x and y are less than 50% ?

If x =20% and y =30% and x and y = 10%
then the expression x+y-100 would result -50% which is nonsense..


Whats wrong with my thinking?
Math Expert
User avatar
V
Joined: 02 Aug 2009
Posts: 7037
Re: X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 11 May 2016, 07:35
2
MorningRunner wrote:
Hi..
Can anyone help me to understand my doubt?
What if x and y are less than 50% ?

If x =20% and y =30% and x and y = 10%
then the expression x+y-100 would result -50% which is nonsense..


Whats wrong with my thinking?


Hi,
you are totally correct with your observation.
The Q is flawed in that it fails to mention clearly that all houses are either suits or painted light blue...

When you take all these house to be atleast ONE of the two groups with few common to the two groups, the Qs will stand, otherwise it will fall apart..

But as the way Q stands, it is FLAWED and you are not likely to see anything of this kind in ACTUALs
_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html


GMAT online Tutor

Senior Manager
Senior Manager
User avatar
G
Joined: 03 Apr 2013
Posts: 278
Location: India
Concentration: Marketing, Finance
GMAT 1: 740 Q50 V41
GPA: 3
GMAT ToolKit User
Re: X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 07 Jul 2016, 19:59
Himalayan wrote:
X percents of the rooms are suits, Y percent of the rooms are painted light blue. Which of the following best represents the least percentage of the light blue painted suits?

A. X-Y
B. Y-X +100
C. 100X-Y
D. X+Y-100
E. 100-XY


The answer is easy..the wording I think..is awkward.. I want Bunuel to respond on this..

The minimum is..0 percent..but if you ask me what is going to be the number of blue painted suits in any case?..I would say (D). But I dont think thats what the question is asking..
_________________

Spread some love..Like = +1 Kudos :)

Target Test Prep Representative
User avatar
P
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 4170
Location: United States (CA)
Re: X percents of the rooms are suits, Y percent of the rooms  [#permalink]

Show Tags

New post 12 Sep 2018, 17:23
Himalayan wrote:
X percents of the rooms are suits, Y percent of the rooms are painted light blue. Which of the following best represents the least percentage of the light blue painted suits?

A. X-Y
B. Y-X +100
C. 100X-Y
D. X+Y-100
E. 100-XY


If we assume there are 100 rooms, we see that x will be the number of suites and y will be the number of rooms that are painted light blue. In order to minimize the number of those that are both suites and painted light blue, we use the formula:

Total = number of suites + number of painted light blue – blue suites + neither blue nor suite

100 = x + y – blue suites + neither blue nor suite

By simple algebra, we have:

Blue suites = x + y + neither – 100

We observe that increasing the number of rooms that are neither light blue nor a suit while keeping everything else the same increases the number of rooms that are both suits and painted light blue. Therefore, to minimize the number of blue suites , we need the number of those that are neither suites nor painted blue to be 0, leaving us with the expression x + y – 100 for the minimum number of rooms that are both suites and painted light blue.

Answer: D
_________________

Scott Woodbury-Stewart
Founder and CEO

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

GMAT Club Bot
Re: X percents of the rooms are suits, Y percent of the rooms &nbs [#permalink] 12 Sep 2018, 17:23
Display posts from previous: Sort by

X percents of the rooms are suits, Y percent of the rooms

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

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®.