It is currently 28 Jun 2017, 04:12

### 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

# DS: Geometry

Author Message
Director
Joined: 07 Nov 2004
Posts: 683

### Show Tags

07 Dec 2004, 16:57
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions

### HideShow timer Statistics

This topic is locked. If you want to discuss this question please re-post it in the respective forum.

DS from Kaplan
Attachments

kap.GIF [ 3.46 KiB | Viewed 1106 times ]

 Kaplan GMAT Prep Discount Codes Magoosh Discount Codes e-GMAT Discount Codes
Intern
Joined: 26 Nov 2004
Posts: 47

### Show Tags

07 Dec 2004, 17:06
I think it should be D.
from both the stems, you could figure out the value of side of a square, and the angle for the arc is 45, so there you go.
Manager
Joined: 09 Sep 2004
Posts: 164

### Show Tags

07 Dec 2004, 17:20
foraj wrote:
I think it should be D.
from both the stems, you could figure out the value of side of a square, and the angle for the arc is 45, so there you go.

Pls explain in itsy bitsy bits! Ta very much!
Intern
Joined: 26 Nov 2004
Posts: 47

### Show Tags

07 Dec 2004, 17:48
AB is the diameter of the circle, and ABCD is a square, these are given in the question.
Stem 1) r=5, so you know the side of square is 10, the area of triangle ADC will be 1/2*10*10, shaded region is area of ADC - area of Arc AT(T is where AC intersects with the circle). Area of Arc is 45/360*2*3.14*5, now you have both.
Stem 2) Similarly as above.
CIO
Joined: 09 Mar 2003
Posts: 463

### Show Tags

07 Dec 2004, 18:05
gayathri wrote:
DS from Kaplan

I'd say D, too.

I think this is hard to very hard.

In order to do it, the plan would be to find the area of the triange, and subtract the little arc piece from it.

Once we have the radius, which is four, we know everything about the square, which has side 8, and the triangle would be 32.

But the question is still about the arc.

For that, we see that the angle of CAD is 45. Therefore, if we drew a line OT (T being where AC hits the circle) we'd have an arc, and the degrees would be double CAD, so AOT is 90 degrees.

If that's true, then we know everything. The area of the whole wedge from AOT is 1/4 the area of the circle (because the arc angle is 90) and we can figure out the area of the triangle AOT because it's a 45 45 90 triangle with side 4.

So the area of the little arc we're subtracting is the area of the whole wedge minus the area of the triangle. Since we can get that, we can get the whole thing.

Same goes for two. With the triangle area, we can work backwards to everything else.
Director
Joined: 07 Nov 2004
Posts: 683

### Show Tags

07 Dec 2004, 18:59
OA is D. Great explanation Ian!
Senior Manager
Joined: 19 Feb 2004
Posts: 413
Location: Lungi

### Show Tags

07 Dec 2004, 19:02
is it A.
A. is sufficient we can find the area of square , triangle and the sector.
B. can give diff values for the base of the triangle and is not sufficient.
Director
Joined: 07 Nov 2004
Posts: 683

### Show Tags

07 Dec 2004, 19:14
batliwala wrote:
is it A.
A. is sufficient we can find the area of square , triangle and the sector.
B. can give diff values for the base of the triangle and is not sufficient.

How do you get different values for the base?
ABCD is a square so AD = DC = x
So if area of ADC = 32
=> x^2/2 =32; x^2 = 64
so x = 8, since x cannot be -8.

=> radius of circle is 4. Same info as A.
Senior Manager
Joined: 19 Feb 2004
Posts: 413
Location: Lungi

### Show Tags

08 Dec 2004, 01:10
, yup agree costly mistake.
08 Dec 2004, 01:10
Display posts from previous: Sort by