Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 30 Sep 2016, 00:34

### 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 June
Open Detailed Calendar

# 50% of the aparments in a certain building have windows and

Author Message
TAGS:

### Hide Tags

Current Student
Joined: 29 Jan 2005
Posts: 5239
Followers: 23

Kudos [?]: 338 [0], given: 0

50% of the aparments in a certain building have windows and [#permalink]

### Show Tags

25 Nov 2005, 09:43
11
This post was
BOOKMARKED
00:00

Difficulty:

75% (hard)

Question Stats:

61% (03:26) correct 39% (02:27) wrong based on 330 sessions

### HideShow timer Statistics

50% of the apartments in a certain building have windows and hardwood floors. 25% of the apartments without windows have hardwood floors. If 40% of the apartments do not have hardwood floors, what percent of the apartments with windows have hardwood floors?

A. 10
B. 16 2/3
C. 40
D. 50
E. 83 1/3
[Reveal] Spoiler: OA
VP
Joined: 30 Sep 2004
Posts: 1488
Location: Germany
Followers: 6

Kudos [?]: 292 [0], given: 0

### Show Tags

25 Nov 2005, 10:04
83 1/3...best way is to construct a matrix...

..........h......no h....total
w.......50..................
no w..0,25x............x
total............40......100

fill in...
_________________

If your mind can conceive it and your heart can believe it, have faith that you can achieve it.

SVP
Joined: 28 May 2005
Posts: 1723
Location: Dhaka
Followers: 7

Kudos [?]: 287 [0], given: 0

### Show Tags

25 Nov 2005, 15:38
yup you need to construct a matrix

X********| Windows'|No Windows'''| total
hardFl****'|50*****''|10*********'|60
Not hardFl*|10******|30*********'|40
Total*****|60******'|40*********'|100

so percent of the apartments with windows have hardwood floors = 50/60 *100

= 83 1/3

_________________

hey ya......

Intern
Joined: 12 Sep 2009
Posts: 4
Followers: 0

Kudos [?]: 4 [3] , given: 2

Re: This one will test your skill for Overlapping Sets concept [#permalink]

### Show Tags

16 Sep 2009, 07:57
3
KUDOS

Here is my working...
a = total windows
b = total of no windows

HW = .5 (given in the problem statement)
(No W,H) = 0.25b
H = 0.6 (given in the problem statement)
No H = 0.4 (deduced as 1 -.06, but this is not needed to solve the problem)

HW + (No W,H) = 0.60
.5+0.25b = 0.60
b = 0.40
Therefore a = 1-b = 1-.40 = 0.60 (proportion of apartments with windows)

Therefore the desired proportion = (HW/a)*100 = (0.5/0.6) * 100 = 83.33% (E).

Manager
Joined: 10 Jul 2009
Posts: 129
Location: Ukraine, Kyiv
Followers: 4

Kudos [?]: 129 [2] , given: 60

Re: This one will test your skill for Overlapping Sets concept [#permalink]

### Show Tags

16 Sep 2009, 10:32
2
KUDOS
E. did it by simple picking numbers and creating a table. check this out.
Attachments

solution.xls [7 KiB]

_________________

Never, never, never give up

VP
Status: There is always something new !!
Affiliations: PMI,QAI Global,eXampleCG
Joined: 08 May 2009
Posts: 1353
Followers: 17

Kudos [?]: 226 [0], given: 10

Re: This one will test your skill for Overlapping Sets concept [#permalink]

### Show Tags

02 May 2011, 02:07
total apartments = 100
with windows and hardwoods = 50
without windows = 50

without windows but having hardwoods = 0.25 *50 = 12.25

12.25 + with windows and hardwoods = 60
with windows and hardwoods = 47.75

% = 47.75 / 50 > 50%
Hence E.
_________________

Visit -- http://www.sustainable-sphere.com/
Promote Green Business,Sustainable Living and Green Earth !!

VP
Status: Far, far away!
Joined: 02 Sep 2012
Posts: 1123
Location: Italy
Concentration: Finance, Entrepreneurship
GPA: 3.8
Followers: 175

Kudos [?]: 1839 [1] , given: 219

Re: 50% of the aparments in a certain building have windows and [#permalink]

### Show Tags

04 Apr 2013, 15:50
1
KUDOS
Tagger wrote:
Still can't get the solution using the Double matrix

Take a look at the image.

X is the percentage of Non-Window, and we know that 25% of that number has Hardwood => 0.25x is in the cell (NW, H) and 0,75x is, of course, in the (NW, NH) cell.
($$0.25x+0.75x=x$$). The tot Hardwood is 60%, and is composed by the first row: $$50+0.25x=60$$ x=40. Ok, we have X, or the tot perc of NonWindows.
Now we know also that $$y+40%=100%$$ and clearly y = 60% => tot perc of W is 60%.This is composed by the cell [Window, Hardwood (50%)] and by the cell [Window, NonHardwood (that must be 10% since 50%+10%=60%)]

And now we have all the data we can have. To answer the question: "what percent of the apartments with windows have hardwood floors?" we must calculate the fraction (apartments with windows and hardwood floors [W,H])/(apartments with windows[W]) = $$\frac{50%}{60%}$$ = $$83 \frac{1}{3}$$

Hope it's clear
Attachments

matrix.png [ 2.63 KiB | Viewed 4744 times ]

_________________

It is beyond a doubt that all our knowledge that begins with experience.

Kant , Critique of Pure Reason

Tips and tricks: Inequalities , Mixture | Review: MGMAT workshop
Strategy: SmartGMAT v1.0 | Questions: Verbal challenge SC I-II- CR New SC set out !! , My Quant

Rules for Posting in the Verbal Forum - Rules for Posting in the Quant Forum[/size][/color][/b]

GMAT Club Legend
Joined: 09 Sep 2013
Posts: 11748
Followers: 529

Kudos [?]: 149 [0], given: 0

Re: This one will test your skill for Overlapping Sets concept [#permalink]

### Show Tags

22 Oct 2013, 00:00
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 11748
Followers: 529

Kudos [?]: 149 [0], given: 0

Re: 50% of the aparments in a certain building have windows and [#permalink]

### Show Tags

27 Apr 2015, 04:22
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
GMAT Club Legend
Joined: 09 Sep 2013
Posts: 11748
Followers: 529

Kudos [?]: 149 [0], given: 0

Re: 50% of the aparments in a certain building have windows and [#permalink]

### Show Tags

31 Jul 2016, 23:15
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________
Re: 50% of the aparments in a certain building have windows and   [#permalink] 31 Jul 2016, 23:15
Similar topics Replies Last post
Similar
Topics:
A certain rectangular window is three times as long as it is wide. If 2 28 Feb 2016, 11:58
A certain ball was dropped from a window 8 meters above a sidewalk. On 2 26 Nov 2015, 05:40
7 In a certain apartment building, there are one-bedroom and two-bedroom 4 23 Feb 2015, 16:52
19 Ben and Shari have invited three other couples to their apar 5 03 Jul 2014, 12:51
5 A certain rectangular window is twice as long as it is wide. 10 17 Dec 2012, 07:21
Display posts from previous: Sort by