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

 It is currently 24 May 2017, 10:53

### 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

# The radius of the front wheels of the cart is half that of

Author Message
CEO
Joined: 21 Jan 2007
Posts: 2747
Location: New York City
Followers: 11

Kudos [?]: 939 [0], given: 4

The radius of the front wheels of the cart is half that of [#permalink]

### Show Tags

24 Oct 2007, 14:23
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

The radius of the front wheels of the cart is half that of the rear wheels. If the circumference of the front wheels is 1 meter and the cart went 1 kilometer, how many revolutions did the rear wheels make?

250/pi
500/pi
250
500
750
VP
Joined: 09 Jul 2007
Posts: 1102
Location: London
Followers: 6

Kudos [?]: 110 [0], given: 0

Re: Challenge - RT = D Cart [#permalink]

### Show Tags

24 Oct 2007, 14:30
bmwhype2 wrote:
The radius of the front wheels of the cart is half that of the rear wheels. If the circumference of the front wheels is 1 meter and the cart went 1 kilometer, how many revolutions did the rear wheels make?

250/pi
500/pi
250
500
750

2Rf=Rb

Sf=1=2pRf ---> Rf=1/2p

Rb=2*1/2p=1/p

Sb=2pRb=2*p*1/p=2m

1km=1000m,
1000/2=500

D
Manager
Joined: 18 Jun 2007
Posts: 55
Followers: 1

Kudos [?]: 7 [0], given: 0

### Show Tags

24 Oct 2007, 19:04

Little circle circumference = 1
2pir = 1 => 1/2pi = r
Radius of big circle = 1/pi
2piR = 2pi/pi = 2
1000meters/2meters = 500meters
SVP
Joined: 29 Aug 2007
Posts: 2476
Followers: 70

Kudos [?]: 774 [0], given: 19

Re: Challenge - RT = D Cart [#permalink]

### Show Tags

24 Oct 2007, 22:17
bmwhype2 wrote:
The radius of the front wheels of the cart is half that of the rear wheels. If the circumference of the front wheels is 1 meter and the cart went 1 kilometer, how many revolutions did the rear wheels make?

250/pi
500/pi
250
500
750

c = 2 pi r = 1
r = 1/2 pi

R = 2(1/2 pi) = 1/pi
C = 2 pi R = 2 pi (1/pi) = 2
# = 1000km/(2 pi R) = 1000km/2 = 500 times
Director
Joined: 09 Aug 2006
Posts: 757
Followers: 1

Kudos [?]: 210 [0], given: 0

Re: Challenge - RT = D Cart [#permalink]

### Show Tags

24 Oct 2007, 22:22
bmwhype2 wrote:
The radius of the front wheels of the cart is half that of the rear wheels. If the circumference of the front wheels is 1 meter and the cart went 1 kilometer, how many revolutions did the rear wheels make?

250/pi
500/pi
250
500
750

D

Circumference of rear wh. = 2 pi * 1/pi = 2 m

Distance = 1000 m

Revs = 1000/2 = 500
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

25 Oct 2007, 09:25
yes I got 500 too... same work as raveshnok
CEO
Joined: 21 Jan 2007
Posts: 2747
Location: New York City
Followers: 11

Kudos [?]: 939 [0], given: 4

Re: Challenge - RT = D Cart [#permalink]

### Show Tags

15 Dec 2007, 15:08
GMAT TIGER wrote:
bmwhype2 wrote:
The radius of the front wheels of the cart is half that of the rear wheels. If the circumference of the front wheels is 1 meter and the cart went 1 kilometer, how many revolutions did the rear wheels make?

250/pi
500/pi
250
500
750

c = 2 pi r = 1
r = 1/2 pi

R = 2(1/2 pi) = 1/pi
C = 2 pi R = 2 pi (1/pi) = 2
# = 1000km/(2 pi R) = 1000km/2 = 500 times

Re: Challenge - RT = D Cart   [#permalink] 15 Dec 2007, 15:08
Display posts from previous: Sort by