Find all School-related info fast with the new School-Specific MBA Forum
Learn more about the recent changes... close

It is currently 25 May 2013, 04:51
Customize  |  Hide

Search
Register
New posts
Unanswered

A car traveling at a certain constant speed takes 2 seconds

  Question banks Downloads My Bookmarks Reviews  
  Oldest Best Reply
Search for:
 
Print view
First unread post
Author Message
TAGS:
Intern
Intern
Joined: 19 Nov 2011
Posts: 8
Followers: 0

Kudos [?]: 2 [0], given: 0

A car traveling at a certain constant speed takes 2 seconds [#permalink] New post 28 Jan 2012, 04:10
00:00

Question Stats:

61% (03:04) correct 38% (04:07) wrong based on 2 sessions
A car traveling at a certain constant speed takes 2 seconds longer to travel 1 kilometer than it would take to travel 1 kilometer at 75 kilometers per hour. At what speed, in kilometers per hour, is the car traveling?

A. 71.5
B. 72
C. 72.5
D. 73
E. 73.5
[Reveal] Spoiler: OA

Last edited by Bunuel on 28 Jan 2012, 04:59, edited 1 time in total.
Added the OA
2 KUDOS received
GMAT Club team member
User avatar
Joined: 02 Sep 2009
Posts: 11627
Followers: 1802

Kudos [?]: 9604 [2] , given: 829

GMAT Tests User CAT Tests
Top Member of the Month
Re: Rate [#permalink] New post 28 Jan 2012, 04:58
2
This post received
KUDOS
RadhaKrishnan wrote:
A car traveling at a certain constant speed takes 2 seconds longer to travel 1 kilometer than it would take to travel 1 kilometer at 75 kilometers per hour. At what speed, in kilometers per hour, is the car traveling?

A. 71.5
B. 72
C. 72.5
D. 73
E. 73.5


Many approaches are possible, one of them:

Let the distance be 1 kilometer.

Time to cover this distance at 75 kilometers per hour is 1/75 hours = 3,600/75 seconds = 48 seconds;
Time to cover this distance at regular speed is 48+2=50 seconds = 50/3,600 hours = 1/72 hours;
So, we get that to cover 1 kilometer 1/72 hours is needed --> regular speed 72 kilometers per hour (rate is a reciprocal of time or rate=distance/time).

Answer: B.
_________________

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. NEW!!!

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set. NEW!!!


What are GMAT Club Tests?
25 extra-hard Quant Tests

Find out what's new at GMAT Club - latest features and updates

Senior Manager
Senior Manager
User avatar
Joined: 23 Oct 2010
Posts: 335
Location: Azerbaijan
Followers: 6

Kudos [?]: 68 [0], given: 67

CAT Tests
Re: A car traveling at a certain constant speed takes 2 seconds [#permalink] New post 30 Jan 2012, 01:11
if 1 h=60*60 sec, then 2 sec =2/60*60=1/1800

1/1800+1/75=25/1800=1/72

since t=D/S and t=1/72 D=1 then S=72
_________________

Happy are those who dream dreams and are ready to pay the price to make them come true

Manager
Manager
Joined: 10 Jan 2010
Posts: 194
Location: Germany
Concentration: Strategy, General Management
Schools: IE '15 (M)
GMAT 1: Q V
GPA: 3
WE: Consulting (Telecommunications)
Followers: 2

Kudos [?]: 15 [0], given: 7

GMAT Tests User
Re: A car traveling at a certain constant speed takes 2 seconds [#permalink] New post 30 Jan 2012, 03:41
B - 72

Original time in seconds: 60*60/75 = 48 --> Car need 48 seconds to travel 1 km
New car needs 2 more seconds to travel 1km --> 50 seconds to travel 1km

Speed (new car): 50 (seconds) / 3600 (1 hour in seconds) = 1 / 72 --> in 1 Minute the car travels 1 / 72. Thus 72km/h
Intern
Intern
Joined: 10 Jan 2013
Posts: 14
Followers: 0

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

Distance [#permalink] New post 11 Feb 2013, 09:34
A car traveling at a certain constant speed takes 2 seconds longer to travel 1 kilometer than it would take to travel 1 kilometer at 75 kilometers per hour. At what speed, in kilometers per hour, is the car traveling?
A. 71.5
B. 72
C. 72.5
D. 73
E. 73.5
GMAT Club team member
User avatar
Joined: 02 Sep 2009
Posts: 11627
Followers: 1802

Kudos [?]: 9604 [0], given: 829

GMAT Tests User CAT Tests
Top Member of the Month
Re: Distance [#permalink] New post 11 Feb 2013, 09:41
4112019 wrote:
A car traveling at a certain constant speed takes 2 seconds longer to travel 1 kilometer than it would take to travel 1 kilometer at 75 kilometers per hour. At what speed, in kilometers per hour, is the car traveling?
A. 71.5
B. 72
C. 72.5
D. 73
E. 73.5


Merging similar topics.

Pleas, search before posting.

Also, please name the topics properly. Rule #3 here: rules-for-posting-please-read-this-before-posting-133935.html
_________________

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory

COLLECTION OF QUESTIONS:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. NEW!!!

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS ; 9 Devil's Dozen!!!; 10 Number Properties set. NEW!!!


What are GMAT Club Tests?
25 extra-hard Quant Tests

Find out what's new at GMAT Club - latest features and updates

Re: Distance   [#permalink] 11 Feb 2013, 09:41
    Similar topics Author Replies Last post
Similar
Topics:
 Popular new posts A car traveling at a certain constant speed takes 2 seconds nocilis 13 02 Feb 2005, 22:41
New posts A car traveling at a certain constant speed takes 2 seconds M8 4 25 Apr 2006, 12:38
New posts Q28: A car traveling at a certain constant speed takes 2 jet1445 3 05 Jun 2007, 20:40
New posts A car traveling at a certain constant speed takes 2 seconds marcodonzelli 6 19 Jan 2008, 07:11
New posts A car traveling at a certain constant speed takes 2 seconds vksunder 2 23 Sep 2008, 07:00
Display posts from previous: Sort by

A car traveling at a certain constant speed takes 2 seconds

  Question banks Downloads My Bookmarks Reviews  
Print view
First unread post

Moderators: Bunuel, VeritasPrepKarishma, IanStewart

Search for:


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®.

Main navigation

GMAT Resources

Partners

MBA Resources

www.gmac.com|www.mba.com