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 500,000 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:

Pat's watch gains an extra 10 seconds every 2 hours. Kim's [#permalink]
24 Mar 2013, 09:47

2

This post was BOOKMARKED

00:00

A

B

C

D

E

Difficulty:

45% (medium)

Question Stats:

61% (02:04) correct
39% (00:55) wrong based on 108 sessions

Pat's watch gains an extra 10 seconds every 2 hours. Kim's watch loses 5 seconds every 3 hours. If both watches are set to correct time at 8 o'clock in the morning and run without interruption, after 72 hours, what will be the difference in time between Pat's watch and Kim's watch?

Re: Pat's watch gains an extra 10 seconds every 2 hours. Kim's [#permalink]
24 Mar 2013, 09:53

2

This post received KUDOS

In 72 hours Pat's watch will gain 360 seconds, since in 2 hours it gains 10 seconds, that means in 1 hour 5 seconds and in 72 hours 72*5 seconds, i.e. 360 seconds or 6 mins. Kim's watch loses 5 seconds in 3 hours, in 72 hours it will loose 72/3 * 5 = 24*5 = 120 seconds = 2 mins. Total difference 6 - (-2, it lost 2 mins ) = 6 + 2 = 8 mins.

Re: Pat's watch gains an extra 10 seconds every 2 hours. Kim's [#permalink]
24 Mar 2013, 13:39

This is how I solved this..

10s/2h, 72/2 -> 36 (and then the /h value x10) -> 36x10 = 360. Go on with /6 -> 6min 5s/3h, 72/3 -> 24 (and then the /h value x5) -> 36x5 = 120. Go on with /6 -> 2 (sine it's a loss it's -2)

-2 to 6 = 8, hence E (I did not get it right first since I personally missed the "loss") _________________

Pat's watch gains an extra 10 seconds every 2 hours. Kim's [#permalink]
14 Jul 2014, 22:17

Bunuel,

This question is using a kind of Relative velocity fundamental, but is put forward in a different manner. Opposite speeds do add up in relative calculations. _________________

Pat's watch gains an extra 10 seconds every 2 hours. Kim's [#permalink]
15 Jul 2014, 01:46

Expert's post

honchos wrote:

Bunuel,

Can you Please solve this question.

Pat's watch gains an extra 10 seconds every 2 hours. Kim's watch loses 5 seconds every 3 hours. If both watches are set to correct time at 8 o'clock in the morning and run without interruption, after 72 hours, what will be the difference in time between Pat's watch and Kim's watch?

(A) 4 min

(B) 6 min

(C) 6 min 40 sec

(D) 7 min 30 sec

(E) 8 min

In 72 hours Pat's watch will gain an extra 72/2*10 = 360 seconds.

In 72 hours Kim's watch will lose 72/3*5 = 120 seconds.

Hence the difference will be 360 + 120 = 480 seconds or 8 minutes.

Re: Pat's watch gains an extra 10 seconds every 2 hours. Kim's [#permalink]
23 Aug 2015, 00:52

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. _________________

Low GPA MBA Acceptance Rate Analysis Many applicants worry about applying to business school if they have a low GPA. I analyzed the low GPA MBA acceptance rate at...

In out-of-the-way places of the heart, Where your thoughts never think to wander, This beginning has been quietly forming, Waiting until you were ready to emerge. For a long...