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

It is currently 25 May 2013, 00:49
Customize  |  Hide

The shaded area is what percentage of the area of the

  Question banks Downloads My Bookmarks Reviews  
Author Message
TAGS:
Current Student
User avatar
Joined: 12 Jun 2008
Posts: 290
Schools: INSEAD Class of July '10
Followers: 5

Kudos [?]: 30 [0], given: 0

GMAT Tests User
Re: Geometry Proportions [#permalink] New post 04 Jul 2008, 16:05
I think it is me who made made a mistake ;)

Actually it is not BC = 2r/cos(37°) but BC = 4r/cos(37°). Same thing BD = 4r/sin(37°)

(hence the factor 4 difference: I wrote radius for diameter...)

Then the area of the parallelogram is BD*BC = 16*r^2/(cos(37°)*sin(37°))

The ratio we want is then \frac{(4-\Pi)cos(37^o)sin(37^o)}{16} (exact answer, no approximation of any kind)

which numerically is about 2.58% :-D
Director
Director
User avatar
Joined: 12 Apr 2008
Posts: 501
Location: Eastern Europe
Schools: Oxford
Followers: 10

Kudos [?]: 130 [0], given: 4

GMAT Tests User
Re: Geometry Proportions [#permalink] New post 04 Jul 2008, 16:11
Hi, jallenmorris,

The last version of the pic., again, does not give sufficient info:
you can change the angle BAD, and obtain different values of parallelogram’s area.

The fact that in your picture B is strictly above D does not help: it could be merely a coincidence. So in the end the picture doesn’t let us to correctly infer that ABD is right triangle. On real GMAT pictures, all measures that intended to be fixed, are explicitly fixed.

So I think this would be somewhat more proper picture:

Attachment:
GMATQuestionBestPicture_edit.gif
GMATQuestionBestPicture_edit.gif [ 6.48 KiB | Viewed 228 times ]


Also, you need to state that ABCD is parallelogram.
SVP
SVP
User avatar
Joined: 30 Apr 2008
Posts: 1900
Location: Oklahoma City
Schools: Hard Knocks
Followers: 25

Kudos [?]: 341 [0], given: 32

GMAT Tests User
Re: Geometry Proportions [#permalink] New post 04 Jul 2008, 20:03
If you read the first post, I do state it's a parallelogram by stating AD || BC and AB || DC.

Attachment:
GmatQuestion_v_3.14.gif
GmatQuestion_v_3.14.gif [ 6.8 KiB | Viewed 214 times ]


greenoak wrote:
Hi, jallenmorris,

The last version of the pic., again, does not give sufficient info:
you can change the angle BAD, and obtain different values of parallelogram’s area.

The fact that in your picture B is strictly above D does not help: it could be merely a coincidence. So in the end the picture doesn’t let us to correctly infer that ABD is right triangle. On real GMAT pictures, all measures that intended to be fixed, are explicitly fixed.

So I think this would be somewhat more proper picture:

Attachment:
The attachment GMATQuestionBestPicture_edit.gif is no longer available


Also, you need to state that ABCD is parallelogram.

_________________

------------------------------------
J Allen Morris
**I'm pretty sure I'm right, but then again, I'm just a guy with his head up his a$$.

Find out what's new at GMAT Club - latest features and updates

Current Student
User avatar
Joined: 12 Jun 2008
Posts: 290
Schools: INSEAD Class of July '10
Followers: 5

Kudos [?]: 30 [0], given: 0

GMAT Tests User
Re: Geometry Proportions [#permalink] New post 06 Jul 2008, 02:19
Oski wrote:
I think it is me who made made a mistake ;)

Question for you english speakers: Is this correct?

Do you say "it is me who made made a mistake" or do you say "it is I who made made a mistake"?

Thanks!
SVP
SVP
User avatar
Joined: 30 Apr 2008
Posts: 1900
Location: Oklahoma City
Schools: Hard Knocks
Followers: 25

Kudos [?]: 341 [0], given: 32

GMAT Tests User
Re: Geometry Proportions [#permalink] New post 06 Jul 2008, 07:35
I believe this is the correct format:

"It is I who made a mistake." - Use I and only 1 "made".
_________________

------------------------------------
J Allen Morris
**I'm pretty sure I'm right, but then again, I'm just a guy with his head up his a$$.

Find out what's new at GMAT Club - latest features and updates

Current Student
User avatar
Joined: 12 Jun 2008
Posts: 290
Schools: INSEAD Class of July '10
Followers: 5

Kudos [?]: 30 [0], given: 0

GMAT Tests User
Re: Geometry Proportions [#permalink] New post 06 Jul 2008, 07:50
jallenmorris wrote:
I believe this is the correct format:

"It is I who made a mistake." - Use I and only 1 "made".

Sorry for the double made ;)

And thank you for your answer for "I" :-D !
SVP
SVP
User avatar
Joined: 30 Apr 2008
Posts: 1900
Location: Oklahoma City
Schools: Hard Knocks
Followers: 25

Kudos [?]: 341 [0], given: 32

GMAT Tests User
Re: Geometry Proportions [#permalink] New post 06 Jul 2008, 07:54
also, realize this....even though the proper form is "It is I who made a mistake." I doubt many native english speakers actually say this. Most people are going to say "It was me that made the mistake." or they'll use any other form of saying it is their fault.
_________________

------------------------------------
J Allen Morris
**I'm pretty sure I'm right, but then again, I'm just a guy with his head up his a$$.

Find out what's new at GMAT Club - latest features and updates

Current Student
User avatar
Joined: 12 Jun 2008
Posts: 290
Schools: INSEAD Class of July '10
Followers: 5

Kudos [?]: 30 [0], given: 0

GMAT Tests User
Re: Geometry Proportions [#permalink] New post 06 Jul 2008, 07:59
jallenmorris wrote:
also, realize this....even though the proper form is "It is I who made a mistake." I doubt many native english speakers actually say this. Most people are going to say "It was me that made the mistake." or they'll use any other form of saying it is their fault.

"It is I who made a mistake" but "It is me that made a mistake"... No wonders I have difficulties with the sentence correction questions...

But thanks for your patience with this ! :-D
Re: Geometry Proportions   [#permalink] 06 Jul 2008, 07:59
    Similar topics Author Replies Last post
Similar
Topics:
New posts What will be the percentage increase in the area of a circle bmwhype2 3 16 Oct 2007, 12:52
New posts What is the area of the shaded figure? mendelay 6 24 Aug 2009, 09:28
New posts What is the area of the shaded region. (attached diagram: a agnok 8 09 Sep 2010, 10:38
New posts 2 EXPERTS_POSTS_IN_THIS_TOPIC What will be the percentage increase in the area of the cube JubtaGubar 6 21 Apr 2012, 02:07
New posts The area of the shaded portion is what percent of the area o emmak 1 15 Feb 2013, 12:23
Display posts from previous: Sort by

The shaded area is what percentage of the area of the

  Question banks Downloads My Bookmarks Reviews  

Go to page   Previous    1   2   [ 28 posts ] 



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

Powered by phpBB © phpBB Group and phpBB SEO

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®.