It is currently 21 Nov 2017, 19:15

### 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

# A bus traveled from its depot to its destination at an average speed

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 42286

Kudos [?]: 132978 [0], given: 12391

A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

15 Jul 2015, 03:26
Expert's post
3
This post was
BOOKMARKED
00:00

Difficulty:

15% (low)

Question Stats:

88% (01:37) correct 12% (01:49) wrong based on 121 sessions

### HideShow timer Statistics

A bus traveled from its depot to its destination at an average speed of 60 kilometers per hour. On its return to the depot along the same route, the bus traveled at an average speed of only 40 kilometers per hour, making the trip 4 hours longer. What is the total distance of the round trip?

A. 360 kilometers
B. 400 kilometers
C. 600 kilometers
D. 800 kilometers
E. 960 kilometers

Kudos for a correct solution.
[Reveal] Spoiler: OA

_________________

Kudos [?]: 132978 [0], given: 12391

Manager
Joined: 14 Sep 2014
Posts: 94

Kudos [?]: 36 [1], given: 51

WE: Engineering (Consulting)
Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

15 Jul 2015, 03:41
1
KUDOS
Let time for first trip be x hrs

For first trip distance travelled = 60x
For round trip distance travelled 40(x+4) = 40x+160

60x = 40x + 160
x = 8 hrs.

Total Round trip distance = 60*8*2 = 960 kilometers

Kudos [?]: 36 [1], given: 51

SVP
Joined: 08 Jul 2010
Posts: 1851

Kudos [?]: 2348 [1], given: 51

Location: India
GMAT: INSIGHT
WE: Education (Education)
Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

15 Jul 2015, 05:44
1
KUDOS
Expert's post
Bunuel wrote:
A bus traveled from its depot to its destination at an average speed of 60 kilometers per hour. On its return to the depot along the same route, the bus traveled at an average speed of only 40 kilometers per hour, making the trip 4 hours longer. What is the total distance of the round trip?

A. 360 kilometers
B. 400 kilometers
C. 600 kilometers
D. 800 kilometers
E. 960 kilometers

Kudos for a correct solution.

The difference of speed (60-40 = 20 Kmph) is causing the delay of 4 hours

Distance = Speed x Time

Case 1: Distance = 60 x T While driving from Depot to Destination
Case 2: Distance = 40 x (T+4) While returning from Destination to Depot

Since the Distance Travelled is same in both cases therefore

60 x T = 40 x (T+4)
i.e. 20 T = 160
i.e. T = 8 Hours

i.e. (One side) Distance = 60 x T = 60 x 8 = 480
Total Distance of the round trip = 480 x 2 = 960 Km

_________________

Prosper!!!
GMATinsight
Bhoopendra Singh and Dr.Sushma Jha
e-mail: info@GMATinsight.com I Call us : +91-9999687183 / 9891333772
Online One-on-One Skype based classes and Classroom Coaching in South and West Delhi
http://www.GMATinsight.com/testimonials.html

22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION

Kudos [?]: 2348 [1], given: 51

Senior Manager
Joined: 28 Jun 2015
Posts: 300

Kudos [?]: 109 [1], given: 47

Concentration: Finance
GPA: 3.5
Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

15 Jul 2015, 05:57
1
KUDOS
Let the distance be D km and T be time taken (in hours).

Now, D/60 = T; D/40 = T+4

D/60 - D/40 = -4
D(40-60/2400) = -4
D(-20/2400) = -4
D = 480 km

So, total distance = 960 km. Ans (E).
_________________

I used to think the brain was the most important organ. Then I thought, look what’s telling me that.

Kudos [?]: 109 [1], given: 47

Manager
Status: Helping People Ace the GMAT
Joined: 16 Jan 2013
Posts: 184

Kudos [?]: 54 [1], given: 4

Location: United States
Concentration: Finance, Entrepreneurship
GMAT 1: 770 Q50 V46
GPA: 3.1
WE: Consulting (Consulting)
Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

15 Jul 2015, 06:07
1
KUDOS
1
This post was
BOOKMARKED
Think about the concepts. The distance for the 2 trips is the same. So if RT = D, then R1T1 = R2T2.

You can now plug in the infromation:

60T = 40 (T + 4).

Solving T = 8

If the time for the first half took 8 hours and the speed was 60km/hour 8 x 60 = 480.

The total distance is then 480 + 480.
_________________

Want to Ace the GMAT with 1 button? Start Here:
GMAT Answers is an adaptive learning platform that will help you understand exactly what you need to do to get the score that you want.

Kudos [?]: 54 [1], given: 4

SVP
Joined: 08 Jul 2010
Posts: 1851

Kudos [?]: 2348 [0], given: 51

Location: India
GMAT: INSIGHT
WE: Education (Education)
Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

15 Jul 2015, 06:27
Bunuel wrote:
A bus traveled from its depot to its destination at an average speed of 60 kilometers per hour. On its return to the depot along the same route, the bus traveled at an average speed of only 40 kilometers per hour, making the trip 4 hours longer. What is the total distance of the round trip?

A. 360 kilometers
B. 400 kilometers
C. 600 kilometers
D. 800 kilometers
E. 960 kilometers

Kudos for a correct solution.

ALTERNATE METHOD

Speed reduces from 60 to 40 during return journey

i.e. New Speed while return (40) = (2/3)*60

But Distance = Speed x Time
But if Distance is multiplied with some factor (2/3 in this case) then Time should be multiplied with reciprocal of that factor (2/3 in this case)
i.e. Distance = (2/3)Speed x (3/2)Time

i.e. Time during return should be (3/2) of previous time
i.e. If Old Time = T
then, New Time during return = (3/2)T

and (3/2)T - T = 4 Hours
i.e. T = 8 Hours
i.e. (One side) Distance = 60x8 or 40x12 = 480
Both ways Distance = 480*2 = 960

_________________

Prosper!!!
GMATinsight
Bhoopendra Singh and Dr.Sushma Jha
e-mail: info@GMATinsight.com I Call us : +91-9999687183 / 9891333772
Online One-on-One Skype based classes and Classroom Coaching in South and West Delhi
http://www.GMATinsight.com/testimonials.html

22 ONLINE FREE (FULL LENGTH) GMAT CAT (PRACTICE TESTS) LINK COLLECTION

Kudos [?]: 2348 [0], given: 51

Veritas Prep GMAT Instructor
Joined: 15 Jul 2015
Posts: 110

Kudos [?]: 78 [1], given: 7

GPA: 3.62
WE: Corporate Finance (Consulting)
Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

15 Jul 2015, 11:31
1
KUDOS
Expert's post
One way to think about this is that the Distance of the two trips is same. Thus, 40t + 4 hours = 60t. Further, since t will be the same on each side of the equation, you can subtract 40t from each side. That leaves you with 4 hours at 40kph, or 160 km = 20t, or t=8 hours. Finally, since the question asks for the distance of the roundtrip, you can find this by 60 x 8 x 2, or 960 km.
_________________

Dennis
Veritas Prep | GMAT Instructor

Get started with Veritas Prep GMAT On Demand for \$199

Veritas Prep Reviews

Kudos [?]: 78 [1], given: 7

Intern
Joined: 04 Nov 2013
Posts: 43

Kudos [?]: 6 [1], given: 10

Concentration: Finance, Strategy
GPA: 4
Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

15 Jul 2015, 20:56
1
KUDOS
Bunuel wrote:
A bus traveled from its depot to its destination at an average speed of 60 kilometers per hour. On its return to the depot along the same route, the bus traveled at an average speed of only 40 kilometers per hour, making the trip 4 hours longer. What is the total distance of the round trip?

A. 360 kilometers
B. 400 kilometers
C. 600 kilometers
D. 800 kilometers
E. 960 kilometers

Kudos for a correct solution.

Distance = Speed x Time

Trip 1: D = 60(x)
Trip 2: D = 40(x+40)

In round trip problems, the distances are the same.

60x=40(x+40)
60x=40x+160
20x=160
x=8

D = 60(8)
D=480
480(2) = 960 km round trip.
_________________

Please kudos if you found this post helpful. I am trying to unlock the tests

Kudos [?]: 6 [1], given: 10

Intern
Joined: 11 Sep 2013
Posts: 7

Kudos [?]: 11 [1], given: 10

Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

15 Jul 2015, 22:52
1
KUDOS
Speed*time=distance
Let time for trip one be x
Trip1- d1= 60*x
Trip2- d2= 40*(x+4)
D1=D2
So x= 8
So d1= 480
d2= 480
Total distance =960 kms
E

Kudos [?]: 11 [1], given: 10

Intern
Joined: 22 Dec 2014
Posts: 44

Kudos [?]: 33 [1], given: 182

Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

17 Jul 2015, 03:29
1
KUDOS
Bunuel wrote:
A bus traveled from its depot to its destination at an average speed of 60 kilometers per hour. On its return to the depot along the same route, the bus traveled at an average speed of only 40 kilometers per hour, making the trip 4 hours longer. What is the total distance of the round trip?

A. 360 kilometers
B. 400 kilometers
C. 600 kilometers
D. 800 kilometers
E. 960 kilometers

Kudos for a correct solution.

Time for bus to travel its route at average speed of 60kph: t
Given the information, we have equation: $$60t=40(t+4)$$ --> $$t=8$$(hrs) --> total distance of the round trip $$=60*8*2=960$$(km)

Kudos [?]: 33 [1], given: 182

Director
Joined: 21 May 2013
Posts: 539

Kudos [?]: 48 [0], given: 492

Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

17 Jul 2015, 11:39
Bunuel wrote:
A bus traveled from its depot to its destination at an average speed of 60 kilometers per hour. On its return to the depot along the same route, the bus traveled at an average speed of only 40 kilometers per hour, making the trip 4 hours longer. What is the total distance of the round trip?

A. 360 kilometers
B. 400 kilometers
C. 600 kilometers
D. 800 kilometers
E. 960 kilometers

Kudos for a correct solution.

Let one way distance=d
Now, d/60+4=d/40
d/40-d/60=4
3d-2d/120=4
d=480
2d=960 km

Kudos [?]: 48 [0], given: 492

Manager
Joined: 20 Jul 2011
Posts: 81

Kudos [?]: 18 [0], given: 17

GMAT 1: 660 Q49 V31
Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

17 Jul 2015, 16:38
Bunuel wrote:
A bus traveled from its depot to its destination at an average speed of 60 kilometers per hour. On its return to the depot along the same route, the bus traveled at an average speed of only 40 kilometers per hour, making the trip 4 hours longer. What is the total distance of the round trip?

A. 360 kilometers
B. 400 kilometers
C. 600 kilometers
D. 800 kilometers
E. 960 kilometers

Kudos for a correct solution.

Two ways to solve this qn: (Maybe many ways)
1. Distance traveled is same in to and fro problems

60 * t = 40 * (t + 4) => Solving for t, t = 8

Distance = 8*60 = 480 (Usually this will be the trap answer). But they have asked for round trip distance. hence 2*D = 960.
Option E

2. Time Difference btw the two trips is 4 hours. This difference is bec of difference in speed.
Hence,
T2 - T1 =4
D/40 - D/60 = 4
Solving for D, D=> 480; 2D => 960.
Option E

Would like to know if there are any standard techniques that can be applied to all Time/Distance/Speed problems.
Thanks

Kudos [?]: 18 [0], given: 17

Math Expert
Joined: 02 Sep 2009
Posts: 42286

Kudos [?]: 132978 [0], given: 12391

Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

19 Jul 2015, 13:04
Bunuel wrote:
A bus traveled from its depot to its destination at an average speed of 60 kilometers per hour. On its return to the depot along the same route, the bus traveled at an average speed of only 40 kilometers per hour, making the trip 4 hours longer. What is the total distance of the round trip?

A. 360 kilometers
B. 400 kilometers
C. 600 kilometers
D. 800 kilometers
E. 960 kilometers

Kudos for a correct solution.

800score Official Solution:

The distance formula is Distance = Rate × Time. To solve this question, set x as the length of time (in hours) for the first trip. The distance to the destination city is 60 × x, where rate = 60 and time = x. The return trip was 4 hours longer, so its distance is 40(x + 4).

Since we know the distances are the same, we can set them equal to each other and solve for x:
60x = 40(x + 4)
60x = 40x + 160
20x = 160
x = 8.

So, the trip took 8 hours, and its distance is 8 × 60 = 480 kilometers. The question asks for the roundtrip distance, so we double the length of the one-way trip: 480 × 2 = 960 kilometers.

The correct answer is choice (E).
_________________

Kudos [?]: 132978 [0], given: 12391

Non-Human User
Joined: 09 Sep 2013
Posts: 15585

Kudos [?]: 283 [0], given: 0

Re: A bus traveled from its depot to its destination at an average speed [#permalink]

### Show Tags

22 Sep 2017, 06:18
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

Kudos [?]: 283 [0], given: 0

Re: A bus traveled from its depot to its destination at an average speed   [#permalink] 22 Sep 2017, 06:18
Display posts from previous: Sort by