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

It is currently 24 May 2019, 14:07

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

On his tirp form Alba to Benton, Julio dorve the first x

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Intern
Intern
avatar
Joined: 14 Sep 2009
Posts: 24
On his tirp form Alba to Benton, Julio dorve the first x  [#permalink]

Show Tags

New post 18 Aug 2010, 21:33
1
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

83% (02:01) correct 17% (02:33) wrong based on 6 sessions

HideShow timer Statistics

Hey everyone,

Here's a DS Gmat prep question that had me stumped. I'd appreciate some good explanations. Thanks!

On his tirp form Alba to Benton, Julio dorve the first x miles at an average rate of 50 miles per hour and the remaining distance at an average rate of 60 miles per hour. How long did it take Julio to drive the first x miles?

(1) On this trip, Julio drove for a total of 10 hours and drove a total of 530 miles.
(2) On this trip, it took Julio 4 more hours has drive the first x miles than to drive the remaining distance

OPEN DISCUSSION OF THIS QUESTION IS HERE: on-his-trip-from-alba-to-benton-julio-drove-the-first-x-104762.html

--== Message from the GMAT Club Team ==--

THERE IS LIKELY A BETTER DISCUSSION OF THIS EXACT QUESTION.
This discussion does not meet community quality standards. It has been retired.


If you would like to discuss this question please re-post it in the respective forum. Thank you!

To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative | Verbal Please note - we may remove posts that do not follow our posting guidelines. Thank you.
Intern
Intern
avatar
Joined: 11 Aug 2010
Posts: 2
Re: On his tirp form Alba to Benton, Julio dorve the first x  [#permalink]

Show Tags

New post 18 Aug 2010, 21:56
A, since by below calculation you can derive the answer -

x/50 + (530-x)/60 = 10

this comes to 350 km

But just by saying first x km took 4 hours more will not solve the purpose, hope i am right and clear
Joined: 31 Dec 1969
Location: Russian Federation
Concentration: Entrepreneurship, International Business
WE: Supply Chain Management (Energy and Utilities)
Re: On his tirp form Alba to Benton, Julio dorve the first x  [#permalink]

Show Tags

New post 18 Aug 2010, 22:00
1
Let the distance between Alba and Benton be 'k'. So, Julio drove the first 'x' miles at a rate of 50 miles per hour and the remaining 'k-x' at a rate of 60 miles per hour. You have to find out the value of x/50.

Statement 1 tells you that x/50 + (k-x)/60 = 10 and k = 530. Using this information you get that x/50 + (530-x)/60 = 10 and you can solve for x (=350). So, x/50 = 350/50 = 7 hours. Sufficient.

Statement 2 tells you that (k-x)/60 - x/50 = 4. You cannot solve for x unless you know the value of k in this statement. So it is insufficient.

So, the answer is A.
Senior Manager
Senior Manager
avatar
Status: Finally Done. Admitted in Kellogg for 2015 intake
Joined: 25 Jun 2011
Posts: 465
Location: United Kingdom
Concentration: International Business, Strategy
GMAT 1: 730 Q49 V45
GPA: 2.9
WE: Information Technology (Consulting)
Re: On his tirp form Alba to Benton, Julio dorve the first x  [#permalink]

Show Tags

New post 13 Nov 2011, 02:50
On his trip from Alba to Bento, Julio drove the first x miles at an average rate of 50 miles per hour and the remaining distance at an average rate of 60 miles per hour, how long did it take Julio to drive the x miles?

(1) On this trip, Julio drove for a total of 10 hours and drove a total of 530 miles.
(2) On this trip, it took Julio 4 more hour to drive the first x miles than to drive the remaining distance.

As the OA was again not provided this is how I solved it. Can someone be please kind enough to let me know whether I am right or wrong?

Here is how I solved it:

Let's say:

Total Distance - D
Time required to travel x miles - T1
Time required to travel D-x miles - T2
Rate to travel x miles - 50mph
R=D/T => 50=x/T1 and therefore x = 50*T1 ----------------------------------------------(1)

R=D/T => 60=D-x/T2 and therefore x = D-60*T2 ------------------------------------------(2)

So now the question becomes what is T1?

Considering Statement 1

T1+T2=10
T2=10-T1 -------------------------------------------------------------------------------(3)
D = 530

Substituting the value of D in equation 2 above

x = 530-60*T2

Considering the total distance is D, we can say Equation 1 is equal to Equation 2 i.e.
50*T1 = 530-60*T2 ----------------------------------------------------------------------(4)

Substituting the value of T2 from equation 3 to equation 4 will give me the value of T1 and therefore is sufficient to answer the question.

Considering Statement 2

Speed to cover first x miles = 50 mph
Let T1 be the time required to cover x miles & D be the total distance

As R=D/T, we know x/T1+4=50 ------------------------(1)
x-D/T1= 60 ------------------------(2)

2 equations and 3 variables therefore insufficient.

Therefore, statement 1 alone is sufficient to answer this question.
_________________
Best Regards,
E.

MGMAT 1 --> 530
MGMAT 2--> 640
MGMAT 3 ---> 610
GMAT ==> 730
Manager
Manager
User avatar
Status: Enjoying the MBA journey :)
Joined: 09 Sep 2011
Posts: 132
Location: United States (DC)
Concentration: General Management, Entrepreneurship
GMAT 1: 710 Q49 V38
WE: Corporate Finance (Other)
Re: On his tirp form Alba to Benton, Julio dorve the first x  [#permalink]

Show Tags

New post 13 Nov 2011, 03:30
Your approach as well as the answer is correct i.e. Statement 1 alone is sufficient to answer this question.

However, I could spot a minor error in your equations for the Statement 2.


You have assumed T1 to be the time required to cover x miles & D to be the total distance

Therefore, equation 1 should be x/T1 = 50 and not x/T1+4=50

Similarly, equation 2 will be (D-x)/(T1-4) = 60 and not x-D/T1 = 60
This is because you have assumed time T1 for the first x miles which is 4 hours more than the time for the remaining distance. Hence the time required to travel the remaining distance should be T1-4 hours i.e. 4 hours less than the previous time required to travel x miles.

Hope this helps. :)

Cheers!
_________________
MBA Candidate 2015 | Georgetown University
McDonough School of Business
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 55271
Re: On his tirp form Alba to Benton, Julio dorve the first x  [#permalink]

Show Tags

New post 14 Aug 2017, 05:29
On his trip from Alba to Benton, Julio drove the first x miles at an average rate of 50 miles per hour and the remaining distance at an average rate of 60 miles per hour. How long did it take Julio to drive the first X miles?

(1) On this trip, Julio drove for a total of 10 hours and a total of 530 miles --> \(total \ time=10=\frac{x}{50}+\frac{530-x}{60}\) --> we have the linear equation with one unknown, so we can solve for \(x\). Sufficient.

(2) On this trip, it took Julio 4 more hours to drive the first x miles than to drive the remaining distance --> \(\frac{x}{50}=\frac{y}{60}+4\), where \(y\) is the remaining distance --> we have the linear equation with two unknowns, so we can not solve for \(x\). Not sufficient.

Answer: A.

OPEN DISCUSSION OF THIS QUESTION IS HERE: on-his-trip-from-alba-to-benton-julio-drove-the-first-x-104762.html

--== Message from the GMAT Club Team ==--

THERE IS LIKELY A BETTER DISCUSSION OF THIS EXACT QUESTION.
This discussion does not meet community quality standards. It has been retired.


If you would like to discuss this question please re-post it in the respective forum. Thank you!

To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative | Verbal Please note - we may remove posts that do not follow our posting guidelines. Thank you.

_________________
GMAT Club Bot
Re: On his tirp form Alba to Benton, Julio dorve the first x   [#permalink] 14 Aug 2017, 05:29
Display posts from previous: Sort by

On his tirp form Alba to Benton, Julio dorve the first x

  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®.