Check GMAT Club Decision Tracker for the Latest School Decision Releases https://gmatclub.com/AppTrack

 It is currently 25 May 2017, 02:44

### 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

# A machine consisting of 3 connected wheels is mixing

 post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
CEO
Joined: 21 Jan 2007
Posts: 2747
Location: New York City
Followers: 11

Kudos [?]: 940 [0], given: 4

A machine consisting of 3 connected wheels is mixing [#permalink]

### Show Tags

19 Oct 2007, 13:58
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.

A machine consisting of 3 connected wheels is mixing concrete. The engine is running at a speed of 60 rpm and the mixer is mixing at a rate of 8 rpm.

What is the diameter of the mixing wheek if the radius of the smaller drive wheel is 2 inches?

12

15

25

30

32
Director
Joined: 22 Aug 2007
Posts: 567
Followers: 1

Kudos [?]: 56 [0], given: 0

Re: PS hard RT=D question [#permalink]

### Show Tags

19 Oct 2007, 14:19
bmwhype2 wrote:
A machine consisting of 3 connected wheels is mixing concrete. The engine is running at a speed of 60 rpm and the mixer is mixing at a rate of 8 rpm.

What is the diameter of the mixing wheek if the radius of the smaller drive wheel is 2 inches?

12

15

25

30

32

i still wonder how is someone who never bothered to look carefully at the structure of concrete mixing machine in his/her entire life supposed to solve this question... and are not there different types of concrete mixing machines...
VP
Joined: 08 Jun 2005
Posts: 1145
Followers: 7

Kudos [?]: 213 [0], given: 0

### Show Tags

19 Oct 2007, 14:31
I would say (D)

Since the smaller circle has radius of 2 then its perimeter is 4pi

every minute it goes a way of 4pi*60 = 240pi

the biggest circle perimeter is unknown 2*pi*r

240*pi = 2*pi*r*8

r = 15

so the diameter is 30

Attachments

untitled.JPG [ 10.56 KiB | Viewed 1156 times ]

Current Student
Joined: 28 Dec 2004
Posts: 3363
Location: New York City
Schools: Wharton'11 HBS'12
Followers: 15

Kudos [?]: 297 [0], given: 2

### Show Tags

20 Oct 2007, 09:42
ahh.. good one..i fell for 15...

30 is correct..we are looking for diam.
CEO
Joined: 21 Jan 2007
Posts: 2747
Location: New York City
Followers: 11

Kudos [?]: 940 [0], given: 4

### Show Tags

19 Dec 2007, 09:04
KillerSquirrel wrote:
I would say (D)

Since the smaller circle has radius of 2 then its perimeter is 4pi

every minute it goes a way of 4pi*60 = 240pi

the biggest circle perimeter is unknown 2*pi*r

240*pi = 2*pi*r*8

r = 15

so the diameter is 30

OA is D 30
19 Dec 2007, 09:04
Display posts from previous: Sort by

# A machine consisting of 3 connected wheels is mixing

 post reply Question banks Downloads My Bookmarks Reviews Important topics

 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®.