At a certain race, two athlets run around a stadium. The : PS Archive
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 22 Jan 2017, 23:34

### 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

# At a certain race, two athlets run around a stadium. The

Author Message
SVP
Joined: 03 Feb 2003
Posts: 1603
Followers: 8

Kudos [?]: 245 [0], given: 0

At a certain race, two athlets run around a stadium. The [#permalink]

### Show Tags

29 Jun 2004, 05:32
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.

At a certain race, two athlets run around a stadium. The first one runs a lap in 6 minutes; the second one—in 10 minutes. If they start running simultaneously, then how long will it take the first athlet to be exacly two laps ahead of the second one?
Senior Manager
Joined: 26 Jan 2004
Posts: 402
Location: India
Followers: 1

Kudos [?]: 1 [0], given: 0

### Show Tags

29 Jun 2004, 05:54
30 minutes.
First athlete will cover 5 laps in 30 minutes.
Second athlete will cover 3 laps in 30 minutes.
Joined: 31 Dec 1969
Location: Russian Federation
Concentration: Technology, Entrepreneurship
GMAT 1: 710 Q49 V0
GMAT 2: 700 Q V
GMAT 3: 740 Q40 V50
GMAT 4: 700 Q48 V38
GMAT 5: 710 Q45 V41
GMAT 6: 680 Q47 V36
GMAT 7: Q42 V44
GMAT 8: Q42 V44
GMAT 9: 740 Q49 V42
GMAT 10: 740 Q V
GMAT 11: 500 Q47 V33
GMAT 12: 670 Q V
WE: Engineering (Manufacturing)
Followers: 0

Kudos [?]: 202 [0], given: 102268

### Show Tags

29 Jun 2004, 19:57
This answer wworks for non integers too!

Speed 1 x time = distance 1
Speed 2 x time = distance 2
n = number of laps

distance 1 - distance 2 = 2 laps

so,

n x laps x 10 - n x laps x 6 = 2 laps (dividing by laps)

10n-6n = 2

4n = 2

n = 0.5 hours = 30 minutes
Senior Manager
Joined: 21 Mar 2004
Posts: 444
Location: Cary,NC
Followers: 3

Kudos [?]: 68 [0], given: 0

### Show Tags

29 Jun 2004, 20:16
Alfred wrote:
This answer wworks for non integers too!

Speed 1 x time = distance 1
Speed 2 x time = distance 2
n = number of laps

distance 1 - distance 2 = 2 laps

so,

n x laps x 10 - n x laps x 6 = 2 laps (dividing by laps)

10n-6n = 2

4n = 2

n = 0.5 hours = 30 minutes

Your answer is a little confusing ( though I am not saying its wrong )
You define n = number of laps

and later say n = 30 mins which is the required time !!!

I think you might have missed something here

- ash
_________________

ash
________________________
I'm crossing the bridge.........

Senior Manager
Joined: 21 Mar 2004
Posts: 444
Location: Cary,NC
Followers: 3

Kudos [?]: 68 [0], given: 0

### Show Tags

29 Jun 2004, 20:30
Here's my attempt.

let slower guy make n laps his vel = 1/10 lap/min

then,faster guy makes n+2 laps his vel = 1/6 lap/min

time taken for this is same for both guys.

n/ (1/10) = (n+2)/(1/6)

10n =6n+12

n=3 , slower guy makes 3 laps, takes 3*10 = 30 mins.

The LCM method is much quicker.
LCM of 6 and 10 gives the time when both guys meet at a point and complete an Integer number of laps.

The edit function has come back ......thank god...( or actually the programmer)

- ash
_________________

ash
________________________
I'm crossing the bridge.........

GMAT Club Legend
Joined: 15 Dec 2003
Posts: 4302
Followers: 40

Kudos [?]: 429 [0], given: 0

### Show Tags

29 Jun 2004, 20:44
30 min.
difference b/w 1/6 and 1/10 is 1/15
1/15*X = 2
X = 30
_________________

Best Regards,

Paul

Senior Manager
Joined: 21 Mar 2004
Posts: 444
Location: Cary,NC
Followers: 3

Kudos [?]: 68 [0], given: 0

### Show Tags

29 Jun 2004, 20:59
I was wondering why I got a wrong answer using relative speed.

Initially,I was using relative speed as 10-6=4
I declare myself a birdbrain !

Thanks Paul.
- ash
_________________

ash
________________________
I'm crossing the bridge.........

SVP
Joined: 03 Feb 2003
Posts: 1603
Followers: 8

Kudos [?]: 245 [0], given: 0

### Show Tags

29 Jun 2004, 22:16
My solution:

D1=D2+2 laps

T*1/6=T*1/10 + 2 (T is the time)

T=30
29 Jun 2004, 22:16
Display posts from previous: Sort by

# At a certain race, two athlets run around a stadium. The

 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®.