Find all School-related info fast with the new School-Specific MBA Forum

It is currently 29 Jul 2015, 02:45
GMAT Club Tests

Close

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
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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Marc traveled from city A to city B covering as much

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
VP
VP
avatar
Joined: 30 Sep 2004
Posts: 1488
Location: Germany
Followers: 4

Kudos [?]: 111 [0], given: 0

Marc traveled from city A to city B covering as much [#permalink] New post 02 May 2005, 11:46
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

Marc traveled from city A to city B covering as much distance in the second part as he did in the first part of this journey. His speed during the second part was twice as that of the speed during the first part of the journey. What is his average speed of journey during the entire travel?
_________________

If your mind can conceive it and your heart can believe it, have faith that you can achieve it.

Senior Manager
Senior Manager
avatar
Joined: 19 Feb 2005
Posts: 486
Location: Milan Italy
Followers: 1

Kudos [?]: 11 [0], given: 0

 [#permalink] New post 02 May 2005, 12:50
total distance= 2d
time A= d/speedA
time B= d/(2*speedA)

timeA+timeB= d/A+d/2A= d*(1/A+1/2A)=d*1/A*3/2=3/2*d/A
average= 2d/(3/2*d/A)

4/3 A :roll:
don't know if choices are actual numbers or functions...
Manager
Manager
avatar
Joined: 21 Mar 2005
Posts: 115
Location: Basel
Followers: 1

Kudos [?]: 6 [0], given: 0

 [#permalink] New post 03 May 2005, 04:33
I agree . My method:
( d1 x V1 + d2 x ( 2 x V1 ) ) / 2 for d = 1
( V1 +2 V1 ) = 3 V1 / 2 => 1.333 V1
VP
VP
avatar
Joined: 30 Sep 2004
Posts: 1488
Location: Germany
Followers: 4

Kudos [?]: 111 [0], given: 0

 [#permalink] New post 03 May 2005, 05:41
OA:

The first part is 1/3rd of the total distance and the second part is 2/3rd of the total distance. He travels at s km/hr speed during the first half and 2s km/hr speed during the second half.

If 3 km is the total distance, then 1 km was traveled at s km/hr and 2 kms was traveled at 2s km/hr speed.

Hence average speed = total distance/total time=3/(1/s)+(2/2s)=3/(4/2s)=3s/2. This, however, = s+2s/2=3s/2 which is the arithmetic mean of the speeds of the two parts.
_________________

If your mind can conceive it and your heart can believe it, have faith that you can achieve it.

Manager
Manager
avatar
Joined: 05 May 2005
Posts: 92
Location: Kyiv, Ukraine
Followers: 1

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

 [#permalink] New post 05 May 2005, 10:31
do you agree with OA? why is it 1/3 and 2/3? it says "as much distance in the second part as he did in the first part of this journey". should not d1=d2?

thanks, guys
VP
VP
avatar
Joined: 30 Sep 2004
Posts: 1488
Location: Germany
Followers: 4

Kudos [?]: 111 [0], given: 0

 [#permalink] New post 05 May 2005, 11:01
july05 wrote:
do you agree with OA? why is it 1/3 and 2/3? it says "as much distance in the second part as he did in the first part of this journey". should not d1=d2?

thanks, guys


i dont agree with the OA for the same reason as you have mentioned. thats why i posted this question.
_________________

If your mind can conceive it and your heart can believe it, have faith that you can achieve it.

Intern
Intern
avatar
Joined: 14 Nov 2004
Posts: 23
Followers: 0

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

 [#permalink] New post 15 May 2005, 04:30
Let the distance of the 2 parts be 'd' each.
Therefore total distance = 2d.

Now since the speed for the first part is half that of the 2nd part the time for the first part should be double that of the 2nd part.Let the time taken therfore be 2t and t.

Avg speed = Total dist/Total time=2d/3t.
  [#permalink] 15 May 2005, 04:30
Display posts from previous: Sort by

Marc traveled from city A to city B covering as much

  Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Privacy Policy| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

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®.