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

It is currently 18 Apr 2014, 05:49

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

How many hours did it take Dale to drive

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Senior Manager
Senior Manager
Status: Do and Die!!
Joined: 15 Sep 2010
Posts: 333
Followers: 1

Kudos [?]: 37 [0], given: 193

How many hours did it take Dale to drive [#permalink] New post 20 Dec 2011, 06:47
00:00
A
B
C
D
E

Difficulty:

  25% (low)

Question Stats:

69% (01:37) correct 30% (00:52) wrong based on 133 sessions
How many hours did it take Dale to drive from A-town to B-town?

(1) If Dale’s average speed for the trip had been three times as fast, the trip would have taken 2 hours.

(2) The distance from A-town to B-town is 100 miles.

can someone please explain, 1) with mathematical expression.
Thanks
[Reveal] Spoiler: OA

_________________

I'm the Dumbest of All !!

1 KUDOS received
Manager
Manager
Status: Meh, I can't take the GMAT before 2017.
Joined: 20 Aug 2011
Posts: 152
Followers: 3

Kudos [?]: 62 [1] , given: 0

Re: How many hours did it take Dale to drive [#permalink] New post 20 Dec 2011, 07:02
1
This post received
KUDOS
Time= distance/speed

let-
distance be d

A.
avg. speed (s1)=d/t1
time taken=t1
t1=d/s1

avg. speed=3s1
time taken=t2
t2=d/3s1

According to given condition
t2-t1=2
d/s1(1-1/3)=2
d/s1=something
Sufficient

Eliminate B, C, & E.

2.
Insufficient

Hence A
_________________

Hit kudos if my post helps you.
You may send me a PM if you have any doubts about my solution or GMAT problems in general.

2 KUDOS received
Magoosh GMAT Instructor
User avatar
Joined: 28 Nov 2011
Posts: 305
Followers: 269

Kudos [?]: 375 [2] , given: 2

GMAT Tests User
Re: How many hours did it take Dale to drive [#permalink] New post 20 Dec 2011, 10:41
2
This post received
KUDOS
Expert's post
The mathematical expression only seems to complicate things and requires quite a few steps. Thinking about the problem logically, on the other hand, can allow you to deal with (1) in a matter of seconds.

If Dale triples his average speed, then he spends 1/3 less time on the trip. Because he spends 2 hours completing the trip at triple the speed, the original trip would have taken him 6 hours. SUFFICIENT

For (2) we are only given the distance between two cities, A and B. Nowhere is there any rate, so we cannot answer the question. INSUFFICIENT

A.
_________________

Christopher Lele
Magoosh Test Prep


Image

Image

2 KUDOS received
Intern
Intern
Joined: 14 Sep 2010
Posts: 24
Followers: 0

Kudos [?]: 6 [2] , given: 4

Re: How many hours did it take Dale to drive [#permalink] New post 20 Dec 2011, 20:16
2
This post received
KUDOS
Statement 1 is sufficient

T = D/S

2 = D/3S

6 = D/S

T = D/S = 6

Statement 2 gives

T = 100/S

so the value of T depends on the unknown value of S. Insufficient.
Senior Manager
Senior Manager
Joined: 12 Oct 2011
Posts: 279
Followers: 0

Kudos [?]: 17 [0], given: 110

Re: How many hours did it take Dale to drive [#permalink] New post 05 Jan 2012, 06:49
Easy one this.
Statement 1 mentions that if he travels at thrice his average speed, he will take 2 hours. Thus he would have taken 6 hours at his average speed. SUFFICIENT.
Statement 2 gives us no information about rate of travel. INSUFFICIENT.
Answer: A
_________________

Consider KUDOS if you feel the effort's worth it

Manager
Manager
User avatar
Joined: 29 Jul 2011
Posts: 112
Location: United States
Followers: 2

Kudos [?]: 28 [0], given: 6

GMAT Tests User
Re: How many hours did it take Dale to drive [#permalink] New post 06 Jan 2012, 17:34
Let d = distance, x = rate. Time = d/x.

1. If 3x rate -> d/3x = 2 hours -> d/x = 6 hours. Suff
2. d = 100. -> d/x = 100/x, but no info on x. Insuff.

A.
_________________

I am the master of my fate. I am the captain of my soul.
Please consider giving +1 Kudos if deserved!

DS - If negative answer only, still sufficient. No need to find exact solution.
PS - Always look at the answers first
CR - Read the question stem first, hunt for conclusion
SC - Meaning first, Grammar second
RC - Mentally connect paragraphs as you proceed. Short = 2min, Long = 3-4 min

Manager
Manager
User avatar
Joined: 23 Feb 2012
Posts: 216
Location: India
Concentration: Finance, Entrepreneurship
Schools: Said
GMAT 1: 710 Q44 V44
GPA: 2.9
WE: Marketing (Computer Software)
Followers: 2

Kudos [?]: 36 [0], given: 22

GMAT Tests User
Re: How many hours did it take Dale to drive [#permalink] New post 10 Mar 2012, 00:16
It's tempting to start putting D-S-T on paper and trying to attempt this. But ChrisLele's solution validated my approach of simply talking my way to the solution!
_________________

If you like it, Kudo it!

"There is no alternative to hard work. If you don't do it now, you'll probably have to do it later. If you didn't need it now, you probably did it earlier. But there is no escaping it."

710 Debrief. Crash and Burn

Re: How many hours did it take Dale to drive   [#permalink] 10 Mar 2012, 00:16
    Similar topics Author Replies Last post
Similar
Topics:
New posts How many hours did it take Helen to drive to her parents sideslip 3 03 May 2006, 18:14
This topic is locked, you cannot edit posts or make further replies. New Experts publish their posts in the topic How many hours did it take Helen to drive from her house to djdela 7 23 Jul 2008, 21:50
New posts How many hours did it take Helen to drive from her house to bmiller0731 1 03 Feb 2009, 14:54
New posts 1 Experts publish their posts in the topic How many hours did it take Helen to drive from her house to changhiskhan 9 26 Mar 2010, 16:00
New posts How many hours did it take helen to drive from her house to mydreammba 2 25 Oct 2011, 23:20
Display posts from previous: Sort by

How many hours did it take Dale to drive

  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®.