Last visit was: 25 Apr 2026, 08:33 It is currently 25 Apr 2026, 08:33
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
User avatar
marcodonzelli
Joined: 22 Nov 2007
Last visit: 22 Aug 2014
Posts: 626
Own Kudos:
Posts: 626
Kudos: 3,263
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
kumarajeet06
Joined: 26 Feb 2007
Last visit: 13 Apr 2008
Posts: 39
Own Kudos:
Posts: 39
Kudos: 14
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
Mishari
Joined: 30 Nov 2006
Last visit: 23 Feb 2015
Posts: 352
Own Kudos:
Location: Kuwait
Concentration: Strategy - Finance
Posts: 352
Kudos: 922
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
marcodonzelli
Joined: 22 Nov 2007
Last visit: 22 Aug 2014
Posts: 626
Own Kudos:
Posts: 626
Kudos: 3,263
Kudos
Add Kudos
Bookmarks
Bookmark this Post
r^2>3 and r^2<6....the area of the circle is Pi*r^2...so it must be more than 3.14*3. the only value over 9.42 is 10.....are we sure OA id D?
User avatar
Mishari
Joined: 30 Nov 2006
Last visit: 23 Feb 2015
Posts: 352
Own Kudos:
Location: Kuwait
Concentration: Strategy - Finance
Posts: 352
Kudos: 922
Kudos
Add Kudos
Bookmarks
Bookmark this Post
marcodonzelli
r^2>3 and r^2<6....the area of the circle is Pi*r^2...so it must be more than 3.14*3. the only value over 9.42 is 10.....are we sure OA id D?


Sorry, I see no reasoning or mathematical logic here.
User avatar
kevincan
User avatar
GMAT Instructor
Joined: 04 Jul 2006
Last visit: 25 Apr 2026
Posts: 1,623
Own Kudos:
Given Kudos: 166
GRE 1: Q170 V170
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
GRE 1: Q170 V170
Posts: 1,623
Kudos: 2,079
Kudos
Add Kudos
Bookmarks
Bookmark this Post
marcodonzelli
r^2>3 and r^2<6....the area of the circle is Pi*r^2...so it must be more than 3.14*3. the only value over 9.42 is 10.....are we sure OA id D?


Note that the area is slightly more than 9.42, but less than 9.5, right?
User avatar
msday
Joined: 25 Dec 2007
Last visit: 09 Jul 2014
Posts: 515
Own Kudos:
Given Kudos: 28
Concentration: General Management
Schools:Harvard '11
GMAT 1: 790 Q51 V48
Posts: 515
Kudos: 64
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Mishari is correct - it's the area of the region between two circles, the larger has a radius of sqrt(6) and the smaller a radius of sqrt(3).
User avatar
marcodonzelli
Joined: 22 Nov 2007
Last visit: 22 Aug 2014
Posts: 626
Own Kudos:
Posts: 626
Kudos: 3,263
Kudos
Add Kudos
Bookmarks
Bookmark this Post
excuse me....if r^2 must be less than 6 and over 3 we get:

A=Pi*r^2....A must be between 9.42 and 18.84...the only integer between this 2 numbers is 10
User avatar
walker
Joined: 17 Nov 2007
Last visit: 25 May 2025
Posts: 2,396
Own Kudos:
Given Kudos: 362
Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40
Expert
Expert reply
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40
Posts: 2,396
Kudos: 10,848
Kudos
Add Kudos
Bookmarks
Bookmark this Post
marcodonzelli
R is the region consisting of all points x,y such that 3<x^2+y^2<6.

marcodonzelli
excuse me....if r^2 must be less than 6 and over 3 we get:
A=Pi*r^2....A must be between 9.42 and 18.84...the only integer between this 2 numbers is 10


You maybe misunderstood problem. R is a ring, bagel, washer, hollow disk, (all words from my dictionary:))... with a fixed area.

To find the area of the region you should extract area of the smaller circle with r=√3 from area of the larger circle with r=√6

Try to draw the region.
User avatar
marcodonzelli
Joined: 22 Nov 2007
Last visit: 22 Aug 2014
Posts: 626
Own Kudos:
Posts: 626
Kudos: 3,263
Kudos
Add Kudos
Bookmarks
Bookmark this Post
yes I definitely misunderstood it.....thanks for your precious help!



Archived Topic
Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Quantitative Questions Forum
Still interested in this question? Check out the "Best Topics" block above for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!