GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 15 Jan 2019, 16:04

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.

Close

Request Expert Reply

Confirm Cancel
Events & Promotions in January
PrevNext
SuMoTuWeThFrSa
303112345
6789101112
13141516171819
20212223242526
272829303112
Open Detailed Calendar
  • $450 Tuition Credit & Official CAT Packs FREE

     January 15, 2019

     January 15, 2019

     10:00 PM PST

     11:00 PM PST

    EMPOWERgmat is giving away the complete Official GMAT Exam Pack collection worth $100 with the 3 Month Pack ($299)
  • The winning strategy for a high GRE score

     January 17, 2019

     January 17, 2019

     08:00 AM PST

     09:00 AM PST

    Learn the winning strategy for a high GRE score — what do people who reach a high score do differently? We're going to share insights, tips and strategies from data we've collected from over 50,000 students who used examPAL.

A car travels from Town A to Town B at an average speed

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

 
Manager
Manager
User avatar
Joined: 28 May 2009
Posts: 144
Location: United States
Concentration: Strategy, General Management
GMAT Date: 03-22-2013
GPA: 3.57
WE: Information Technology (Consulting)
GMAT ToolKit User
A car travels from Town A to Town B at an average speed  [#permalink]

Show Tags

New post 05 Jan 2013, 17:08
1
4
00:00
A
B
C
D
E

Difficulty:

  15% (low)

Question Stats:

78% (01:47) correct 22% (01:10) wrong based on 372 sessions

HideShow timer Statistics

A car travels from Town A to Town B at an average speed of 40 miles per hour, and returns immediately along the same route at an average speed of 50 miles per hour. What is the average speed in miles per hour for the round-trip?

(A) \(45\frac{4}{9}\) mph

(B) 44 mph

(C) 45 mph

(D) \(44\frac{4}{9}\) mph

(E) \(44\frac{1}{9}\) mph

_________________

New to GMAT Club? Start here

Kindle Flashcards - Quant (Official Gmat Club, miguemick's Quant topics), and Verbal (Official Gmat Club) - in Kindle (azw3) format

Most Helpful Community Reply
Senior Manager
Senior Manager
User avatar
Joined: 27 Jun 2012
Posts: 372
Concentration: Strategy, Finance
Schools: Haas EWMBA '17
Re: A car travels from Town A to Town B at an average speed  [#permalink]

Show Tags

New post 05 Jan 2013, 17:47
4
1
Using "Pick numbers" strategy, assume total distance as 200 miles. (LCM of 40 & 50)

Time taken to travel from A to B = 200/40 = 5 hours
Time taken to travel from B to A = 200/50 = 4 hours

\(Average(speed) = \frac{{Total (Distance) }}{{ Total (Time) }}= \frac{(200+200)}{(5+4)} = \frac{400}{9} = 44 \frac{4}{9}\)

Hence Choice(D).
_________________

Thanks,
Prashant Ponde

Tough 700+ Level RCs: Passage1 | Passage2 | Passage3 | Passage4 | Passage5 | Passage6 | Passage7
Reading Comprehension notes: Click here
VOTE GMAT Practice Tests: Vote Here
PowerScore CR Bible - Official Guide 13 Questions Set Mapped: Click here
Finance your Student loan through SoFi and get $100 referral bonus : Click here

General Discussion
e-GMAT Representative
User avatar
P
Joined: 02 Nov 2011
Posts: 2795
Re: A car travels from Town A to Town B at an average speed  [#permalink]

Show Tags

New post 08 Jan 2013, 01:07
1
2
megafan wrote:
A car travels from Town A to Town B at an average speed of 40 miles per hour, and returns immediately along the same route at an average speed of 50 miles per hour. What is the average speed in miles per hour for the round-trip?

(A) \(45\frac{4}{9}\) mph

(B) 44 mph

(C) 45 mph

(D) \(44\frac{4}{9}\) mph

(E) \(44\frac{1}{9}\) mph


Hi,

This is a classic question on Speed, time, & distance.

1. When time traveled in each segment is constant, then average speed is simple mean of speeds.

2. When distance traveled in each segment is constant, then average speed is reciprocal of simple mean of reciprocal of speeds. It is basically called Harmonic mean.

So this question falls in the category of 2.

=> So, average speed = Reciprocal of mean of reciprocals of 40 & 50.

=> Average speed = Reciprocal of mean of 1/40 & 1/50.

=> Average speed = Reciprocal of (1/40 + 1/50)/2 = Reciprocal of (5+4)/400 = 44 4/9 .

-Shalabh
_________________








Everything you need to ace the GMAT and more
Basics of the GMAT
GMAT Exam Strategies
GMAT Study Plans
GMAT Verbal Subject Matter
GMAT AWA & IR




| '4 out of Top 5' Instructors on gmatclub | 70 point improvement guarantee | www.e-gmat.com

SVP
SVP
User avatar
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1823
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)
Re: A car travels from Town A to Town B at an average speed  [#permalink]

Show Tags

New post 14 Jan 2015, 00:22
1
\(Average(speed) = \frac{{Total (Distance) }}{{ Total (Time)}}\)

Let the distance between Town A & Town B = 1

Setting up the equation:

Average speed \(= \frac{1+1}{\frac{1}{40} + \frac{1}{50}} = \frac{400}{9} = 44\frac{4}{9}\)
_________________

Kindly press "+1 Kudos" to appreciate :)

Manager
Manager
User avatar
S
Joined: 22 Nov 2016
Posts: 208
Location: United States
Concentration: Leadership, Strategy
GPA: 3.4
Reviews Badge
Re: A car travels from Town A to Town B at an average speed  [#permalink]

Show Tags

New post 26 Jun 2017, 15:11
Pick a multiple of 40 and 50 as the distance. 200 is a good number.
Hence the average speed is 400/9 = 44 4/9, D
_________________

Kudosity killed the cat but your kudos can save it.

Director
Director
avatar
S
Joined: 12 Nov 2016
Posts: 731
Location: United States
Schools: Yale '18
GMAT 1: 650 Q43 V37
GRE 1: Q157 V158
GPA: 2.66
Re: A car travels from Town A to Town B at an average speed  [#permalink]

Show Tags

New post 13 Aug 2017, 12:06
megafan wrote:
A car travels from Town A to Town B at an average speed of 40 miles per hour, and returns immediately along the same route at an average speed of 50 miles per hour. What is the average speed in miles per hour for the round-trip?

(A) \(45\frac{4}{9}\) mph

(B) 44 mph

(C) 45 mph

(D) \(44\frac{4}{9}\) mph

(E) \(44\frac{1}{9}\) mph


This is really like an approximation question and round trip question jumbled into one. Anyways, because this is a round trip question the distances for both trips are the same... mathematically that means

distance 1 = 40 (t)
distance 2= 50 (t)

We can just plug in a random value like 200

200= 40t
t=5

200=50t
t=4

Total Distance= Avgspeed * Total Time
400= avgsped* 9
400/9= 44.4444444.. round to closet value

44 4/9

D
Intern
Intern
avatar
B
Joined: 29 May 2017
Posts: 2
Schools: Booth '20
Re: A car travels from Town A to Town B at an average speed  [#permalink]

Show Tags

New post 24 Aug 2017, 21:11
A MOTOR TRAVEL WITH AN AVERAGE SPEED OF 49/HOUR FOR 3 HOURS THEN AN avreage speed of 99/ hour at spped of 39/ 2 hours
Retired Moderator
User avatar
P
Status: The best is yet to come.....
Joined: 10 Mar 2013
Posts: 497
GMAT ToolKit User
Re: A car travels from Town A to Town B at an average speed  [#permalink]

Show Tags

New post 05 Dec 2017, 02:22
egmat wrote:
megafan wrote:
A car travels from Town A to Town B at an average speed of 40 miles per hour, and returns immediately along the same route at an average speed of 50 miles per hour. What is the average speed in miles per hour for the round-trip?

(A) \(45\frac{4}{9}\) mph

(B) 44 mph

(C) 45 mph

(D) \(44\frac{4}{9}\) mph

(E) \(44\frac{1}{9}\) mph


Hi,

This is a classic question on Speed, time, & distance.

1. When time traveled in each segment is constant, then average speed is simple mean of speeds.

2. When distance traveled in each segment is constant, then average speed is reciprocal of simple mean of reciprocal of speeds. It is basically called Harmonic mean.

So this question falls in the category of 2.

=> So, average speed = Reciprocal of mean of reciprocals of 40 & 50.

=> Average speed = Reciprocal of mean of 1/40 & 1/50.

=> Average speed = Reciprocal of (1/40 + 1/50)/2 = Reciprocal of (5+4)/400 = 44 4/9 .

-Shalabh
When distance traveled in each segment is constant, then average speed simply be \(\frac{2xy}{x+y}\), where x and y are speeds.\(\frac{2*40*50}{40+50}\) = \(44\frac{4}{9}\)
_________________

Hasan Mahmud

GMAT Club Bot
Re: A car travels from Town A to Town B at an average speed &nbs [#permalink] 05 Dec 2017, 02:22
Display posts from previous: Sort by

A car travels from Town A to Town B at an average speed

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


Copyright

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

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

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®.