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

 It is currently 09 Feb 2016, 17:03

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# M07-11 - GMAT club test

Author Message
Intern
Joined: 30 Jul 2012
Posts: 3
Followers: 0

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

M07-11 - GMAT club test [#permalink]  11 Sep 2012, 18:48
1
KUDOS
A train traveling at a certain constant speed takes 30 seconds longer to travel 2 kilometers than it would take to travel 4 kilometers at 120 kilometers per hour. At what speed, in kilometers per hour, is the train traveling?
a) 40
b)48
c)80
d)96
e) 120

There is some problem with my understanding of this problem and the way it is solved in official answer. This is what I understood from the problem:
A train covers 4 kms @120kmph in certain time T secs.
Now, how much is the speed (in Kmph) of the train it it covers 2 Kms in (T + 30)secs?

If this understanding is correct then the answer is b) 48. But as per the official solution the answer is c) 80. I think as per my understanding b) is correct but the question is: Is my understanding correct? And if not then what does the question really means?
Senior Manager
Joined: 11 May 2011
Posts: 373
Location: US
Followers: 3

Kudos [?]: 76 [0], given: 46

Re: M07-11 - GMAT club test [#permalink]  11 Sep 2012, 19:34
akashv wrote:
A train traveling at a certain constant speed takes 30 seconds longer to travel 2 kilometers than it would take to travel 4 kilometers at 120 kilometers per hour. At what speed, in kilometers per hour, is the train traveling?
a) 40
b)48
c)80
d)96
e) 120

There is some problem with my understanding of this problem and the way it is solved in official answer. This is what I understood from the problem:
A train covers 4 kms @120kmph in certain time T secs.
Now, how much is the speed (in Kmph) of the train it it covers 2 Kms in (T + 30)secs?

If this understanding is correct then the answer is b) 48. But as per the official solution the answer is c) 80. I think as per my understanding b) is correct but the question is: Is my understanding correct? And if not then what does the question really means?

I interpreted the question exactly what you've described above. Hence, I think, your understanding is correct.
4 kms @120kmph = 120sec
Train time = 120+30 sec. Hence, 2 km in 150sec = 48Km/hr.

Can you post the OE?

Cheers!
_________________

-----------------------------------------------------------------------------------------
What you do TODAY is important because you're exchanging a day of your life for it!
-----------------------------------------------------------------------------------------

Intern
Joined: 11 May 2010
Posts: 3
Followers: 0

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

Re: M07-11 - GMAT club test [#permalink]  11 Sep 2012, 21:09
I too got the answer as 48 km/hr. here is how:

Let the speed be x km/hr. Equating the times in km/hr we get
$$\frac{2}{x} = \frac{4}{120} + \frac{30}{3600}$$
$$\frac{2}{x} = \frac{1}{24}$$
$$x= 48$$

IMO, for the OA to be true the question should read "30 seconds less to travel 2 kilometers" OR "2km at 120km/hr" unless I am missing something.
Math Expert
Joined: 02 Sep 2009
Posts: 31288
Followers: 5352

Kudos [?]: 62275 [1] , given: 9445

Re: M07-11 - GMAT club test [#permalink]  12 Sep 2012, 01:32
1
KUDOS
Expert's post
akashv wrote:
A train traveling at a certain constant speed takes 30 seconds longer to travel 2 kilometers than it would take to travel 4 kilometers at 120 kilometers per hour. At what speed, in kilometers per hour, is the train traveling?
a) 40
b)48
c)80
d)96
e) 120

There is some problem with my understanding of this problem and the way it is solved in official answer. This is what I understood from the problem:
A train covers 4 kms @120kmph in certain time T secs.
Now, how much is the speed (in Kmph) of the train it it covers 2 Kms in (T + 30)secs?

If this understanding is correct then the answer is b) 48. But as per the official solution the answer is c) 80. I think as per my understanding b) is correct but the question is: Is my understanding correct? And if not then what does the question really means?

Edited the question. Thank you. +1.
_________________
Re: M07-11 - GMAT club test   [#permalink] 12 Sep 2012, 01:32
Similar topics Replies Last post
Similar
Topics:
GMAT club test split 1 10 Nov 2009, 13:11
GMAT club tests....difficulty 3 08 Sep 2009, 10:08
Error on gmat club tests 3 21 Aug 2009, 14:40
GMAT CLub Tests Quants 1 11 May 2009, 04:51
10 GMAT Club Tests 48 23 Oct 2008, 03:51
Display posts from previous: Sort by

# M07-11 - GMAT club test

Moderators: Bunuel, WoundedTiger

 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®.