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.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 350,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Marla starts running around a circular track at the same [#permalink]
16 Mar 2012, 06:55

5

This post was BOOKMARKED

00:00

A

B

C

D

E

Difficulty:

25% (medium)

Question Stats:

75% (03:17) correct
25% (01:33) wrong based on 211 sessions

Marla starts running around a circular track at the same time Nick starts walking around the same circular track. Marla completes 32 laps around the track per hour and Nick completes 12 laps around the track per hour. How many minutes after Marla and Nick begin moving will Marla have completed 4 more laps around the track than Nick?

Re: Marla starts running around a circular track at the same [#permalink]
16 Mar 2012, 08:26

4

This post received KUDOS

Expert's post

enigma123 wrote:

Marla starts running around a circular track at the same time Nick starts walking around the same circular track. Marla completes 32 laps around the track per hour and Nick completes 12 laps around the track per hour. How many minutes after Marla and Nick begin moving will Marla have completed 4 more laps around the track than Nick?

(A) 5 (B) 8 (C) 12 (D) 15 (E) 20

How to do this guys?

Marla completes 32-20=20 more laps in 1 hour. Marla to complete 4 (20/5=4) more laps will need 1/5 hours, which is 12 minutes.

Re: Marla starts running around a circular track at the same [#permalink]
16 Mar 2012, 10:00

Marla completes 32laps/60min, Nick completes 12laps/60mins. After x mins Marla would have completed 4 laps more than Nick had completed. x((32-12)/60) = 4, x*20/60 = 4, x = 12 mins.

Re: Marla starts running around a circular track at the same [#permalink]
16 Mar 2012, 15:53

Expert's post

enigma123 wrote:

Bunuel - how did you get this?

Marla to complete 4 (20/5=4) more laps will need 1/5 hours, which is 12 minutes.

Since Marla completes 20 more laps in 1 hour, then to complete 1/5 th of 20 laps (4 laps) she will need 1/5 th of an hour, which is 12 minutes. _________________

Re: Marla starts running around a circular track at the same [#permalink]
12 Apr 2012, 03:35

1

This post received KUDOS

1

This post was BOOKMARKED

Maria's rate - 32 laps per hour --> 32/60 laps/min Nick's rate - 12 laps per hour --> 12/60 laps/min

lets set equations:

32/60*t=4 (since Maria had to run 4 laps before Nick would start) 12/60*t=0 (Hick has just started and hasn't run any lap yet) ----------------------------------- (32/60-12/60)*t=4-0 (since Nick was chasing Maria) t=12 min needed Maria to run 4 laps

Re: Marla starts running around a circular track at the same [#permalink]
23 Apr 2012, 20:50

I also got C (12).

t= time 32 laps per hour * t = 12 laps per hour * t + 4 laps

32t = 12t + 4 20t = 4 t= 1/5 hr

1/5(60min)= 12 mins

I believe the recommended strategy is to change to minutes right away but in this situation I found it easier to do it at the end because of how the rates simplified per minute.

Re: Marla starts running around a circular track at the same [#permalink]
02 May 2014, 02:43

Bunuel wrote:

enigma123 wrote:

Bunuel - how did you get this?

Marla to complete 4 (20/5=4) more laps will need 1/5 hours, which is 12 minutes.

Since Marla completes 20 more laps in 1 hour, then to complete 1/5 th of 20 laps (4 laps) she will need 1/5 th of an hour, which is 12 minutes.

I believe you used the concept of relative speed over here as well Bunuel . Isn't it so ? Relative speed of Bunue is 20 laps/hr so 4 laps in 1/5 of an hr = 12 minutes

gmatclubot

Re: Marla starts running around a circular track at the same
[#permalink]
02 May 2014, 02:43

Originally, I was supposed to have an in-person interview for Yale in New Haven, CT. However, as I mentioned in my last post about how to prepare for b-school interviews...

Hi Starlord, As far as i'm concerned, the assessments look at cognitive and emotional traits - they are not IQ tests or skills tests. The games are actually pulled from...

Interested in applying for an MBA? In the fourth and final part of our live QA series with guest expert Chioma Isiadinso, co-founder of consultancy Expartus and former admissions...

The 2015 Pan American Games and more than 6,000 athletes have come to Toronto. With them they have brought a great positive vibe and it made me think...