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

 It is currently 21 Jun 2018, 03:36

### 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

# It took the bus 4 hours to get from town A to town B. What

Author Message
Current Student
Joined: 11 May 2008
Posts: 551
It took the bus 4 hours to get from town A to town B. What [#permalink]

### Show Tags

02 Aug 2008, 02:45
It took the bus 4 hours to get from town A to town B. What was the average speed of the bus for the trip?

1.In the first 2 hours the bus covered 100 miles
2.The average speed of the bus for the first half of the distance was twice its speed for the second half

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

This is not a quality discussion. 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.
Director
Joined: 27 May 2008
Posts: 531

### Show Tags

02 Aug 2008, 06:57
arjtryarjtry wrote:
It took the bus 4 hours to get from town A to town B. What was the average speed of the bus for the trip?

1.In the first 2 hours the bus covered 100 miles
2.The average speed of the bus for the first half of the distance was twice its speed for the second half

average speed = total distance / total time = d/4

so we have to find out d

statement 1 : we dont know the distance the bus covered in second two hours.. not suff
statement 2 : d/(2t1) = 2d/(2t2)
t2 = 2t1
we know t1+t2 = 4
so t1 = 4/3
and t2 = 8/3
still we cant find d ... so not suff

combine two statements

distance covered in 2 hours = distance covered in t1 (4/3) hours + distance covered in (2-4/3) hours
100 = d/2 + d/(2t2) * (2-4/3)
100 = d/2 + 3d/(2*8) * ((6-4)/3)
100 = d/2 + d/8

suff... actually no need to solve it. we know we can find d and the average speed.... Option C
Current Student
Joined: 11 May 2008
Posts: 551

### Show Tags

02 Aug 2008, 10:33
durgesh79 wrote:
arjtryarjtry wrote:
It took the bus 4 hours to get from town A to town B. What was the average speed of the bus for the trip?

1.In the first 2 hours the bus covered 100 miles
2.The average speed of the bus for the first half of the distance was twice its speed for the second half

average speed = total distance / total time = d/4

so we have to find out d

statement 1 : we dont know the distance the bus covered in second two hours.. not suff
statement 2 : d/(2t1) = 2d/(2t2)
t2 = 2t1
we know t1+t2 = 4
so t1 = 4/3
and t2 = 8/3
still we cant find d ... so not suff

combine two statements

distance covered in 2 hours = distance covered in t1 (4/3) hours + distance covered in (2-4/3) hours
100 = d/2 + d/(2t2) * (2-4/3)
100 = d/2 + 3d/(2*8) * ((6-4)/3)
100 = d/2 + d/8

suff... actually no need to solve it. we know we can find d and the average speed.... Option C

i didnt get the simplification part.. kindly explain
Director
Joined: 27 May 2008
Posts: 531

### Show Tags

02 Aug 2008, 10:49
arjtryarjtry wrote:
durgesh79 wrote:
arjtryarjtry wrote:
It took the bus 4 hours to get from town A to town B. What was the average speed of the bus for the trip?

1.In the first 2 hours the bus covered 100 miles
2.The average speed of the bus for the first half of the distance was twice its speed for the second half

average speed = total distance / total time = d/4

so we have to find out d

statement 1 : we dont know the distance the bus covered in second two hours.. not suff
statement 2 : d/(2t1) = 2d/(2t2)
t2 = 2t1
we know t1+t2 = 4
so t1 = 4/3
and t2 = 8/3
still we cant find d ... so not suff

combine two statements

distance covered in 2 hours = distance covered in t1 (4/3) hours + distance covered in (2-4/3) hours
100 = d/2 + d/(2t2) * (2-4/3)
100 = d/2 + 3d/(2*8) * ((6-4)/3)
100 = d/2 + d/8

suff... actually no need to solve it. we know we can find d and the average speed.... Option C

i didnt get the simplification part.. kindly explain

distance covered in first 2 hours = 100 (as per statement 1)
distance covered in first 4/3 hours = d/2 (as per statement 2)
distance covered in first (2-4/3) hours = average speed during this journey * time
= 3d / (2*8) * (2 - 4/3) ------> we know that for second half of the journey the time taken is 8/3 from statement 2
= d/8

so 100 = d/2 + d/8
Director
Joined: 27 May 2008
Posts: 531

### Show Tags

05 Aug 2008, 02:08
EDIT : Just found this question in GMAT club tests.. and now i'd like to correct myself

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

This is not a quality discussion. 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.
Re: DATA INSUFF..   [#permalink] 05 Aug 2008, 02:08
Display posts from previous: Sort by

# It took the bus 4 hours to get from town A to town B. What

Moderator: chetan2u

 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®.