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

 It is currently 23 May 2019, 04:03

### 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

# The figure above shows a cord around two circular disks. If

Author Message
VP
Joined: 22 Nov 2007
Posts: 1027
The figure above shows a cord around two circular disks. If  [#permalink]

### Show Tags

01 Dec 2007, 11:38
3
00:00

Difficulty:

(N/A)

Question Stats:

50% (00:00) correct 50% (00:00) wrong based on 12 sessions

### HideShow timer Statistics

The figure above shows a cord around two circular disks. If the radii of the two disks are 80 centimeters and 60 centimeters, respectively, what is the total length, in centimeters, of the cord?

(A) 210π

(B) 210π + 280
(C) 280π

(D) 280π + 80
(E) 280π + 280

--== Message from the GMAT Club Team ==--

THERE IS LIKELY A BETTER DISCUSSION OF THIS EXACT QUESTION.
This discussion does not meet community quality standards. It has been retired.

If you would like to discuss this question please re-post it in the respective forum. Thank you!

To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative | Verbal Please note - we may remove posts that do not follow our posting guidelines. Thank you.

Attachments

pic.doc [23.5 KiB]

File comment: use your imagination in watching my pic!
pic.doc [23.5 KiB]

Manager
Joined: 28 Apr 2008
Posts: 108

### Show Tags

09 Jun 2008, 07:57
1

160pi*3/4 +120pi*3/4 + 2*80+2*60= 210pi+280
Director
Joined: 14 Oct 2007
Posts: 717
Location: Oxford
Schools: Oxford'10

### Show Tags

10 Jun 2008, 04:18
marcodonzelli wrote:
The figure above shows a cord around two circular disks. If the radii of the two disks are 80 centimeters and 60 centimeters, respectively, what is the total length, in centimeters, of the cord?

(A) 210π

(B) 210π + 280
(C) 280π

(D) 280π + 80
(E) 280π + 280

another B
basically 3/4 of the circumference of each circle + 2*radius of each circle

= 120pi + 90pi + 160 + 120
= 210pi + 280
Current Student
Joined: 28 Dec 2004
Posts: 3157
Location: New York City
Schools: Wharton'11 HBS'12

### Show Tags

10 Jun 2008, 07:37

haha...

just kidding..but if you could draw it again more acurately then it would be great!

however I will go with B

120pi+160+90pi+120=210pi+280
Director
Joined: 01 Jan 2008
Posts: 582

### Show Tags

10 Jun 2008, 08:09
3/4*(2*pi*R + 2*pi*r) + 2*(R + r) -> B
Intern
Joined: 10 Sep 2011
Posts: 6

### Show Tags

10 Sep 2011, 06:56
3
important thing where i got stuck...
i found this on another site..its really help full.

I feel we are not supposed to take the literal meaning of the term "cord" {lineseg that lies inside the cirlce with its ends lieing on the circle"} [color=#FF4040]as its meaning but as a piece of wire/some material that goes around the 2 circles[/color].

so.........

Since the tangents form squares with the radii.

the total length as tangents = 2*80+2*60 = 280

and the total lenght wound around the circles = 270deg/360deg * 2*pi*80
=120pi

for the second circle similarly 90pi
therfore 210pi+280
Manager
Joined: 20 Nov 2010
Posts: 139

### Show Tags

18 Sep 2011, 16:20
What is OA and source.
_________________
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
MGMAT 6 650 (51,31) on 31/8/11
MGMAT 1 670 (48,33) on 04/9/11
MGMAT 2 670 (47,34) on 07/9/11
MGMAT 3 680 (47,35) on 18/9/11
GMAT Prep1 680 ( 50, 31) on 10/11/11

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
CR notes
http://gmatclub.com/forum/massive-collection-of-verbal-questions-sc-rc-and-cr-106195.html#p832142
http://gmatclub.com/forum/1001-ds-questions-file-106193.html#p832133
http://gmatclub.com/forum/gmat-prep-critical-reasoning-collection-106783.html
http://gmatclub.com/forum/how-to-get-6-0-awa-my-guide-64327.html
http://gmatclub.com/forum/how-to-get-6-0-awa-my-guide-64327.html?hilit=chineseburned
Non-Human User
Joined: 09 Sep 2013
Posts: 10996
Re: The figure above shows a cord around two circular disks. If  [#permalink]

### Show Tags

16 Aug 2017, 00:27
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.

--== Message from the GMAT Club Team ==--

THERE IS LIKELY A BETTER DISCUSSION OF THIS EXACT QUESTION.
This discussion does not meet community quality standards. It has been retired.

If you would like to discuss this question please re-post it in the respective forum. Thank you!

To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative | Verbal Please note - we may remove posts that do not follow our posting guidelines. Thank you.

_________________
Re: The figure above shows a cord around two circular disks. If   [#permalink] 16 Aug 2017, 00:27
Display posts from previous: Sort by