GMAT Question of the Day: Daily via email | Daily via Instagram New to GMAT Club? Watch this Video

 It is currently 03 Apr 2020, 19:06 ### 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

#### Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.  # A car travels the first one-third of a certain distance with a speed

Author Message
TAGS:

### Hide Tags

Math Expert V
Joined: 02 Sep 2009
Posts: 62496
A car travels the first one-third of a certain distance with a speed  [#permalink]

### Show Tags 00:00

Difficulty:   35% (medium)

Question Stats: 67% (02:10) correct 33% (01:22) wrong based on 6 sessions

### HideShow timer Statistics

A car travels the first one-third of a certain distance with a speed of 10 kmph, the next onethird of the distance with a speed of 20 kmph and the last one-third distance at 60 kmph. Find the average speed of the car for the whole journey.

A. 18 kmph
B. 20 kmph
C. 25 kmph
D. 30 kmph
E. 40 kmph

_________________
CrackVerbal Quant Expert G
Joined: 12 Apr 2019
Posts: 478
Re: A car travels the first one-third of a certain distance with a speed  [#permalink]

### Show Tags

Since 1/3rd of the distance is to be taken, let us take the total distance to be 3d kms. There are 3 segments each of d kms then.

For the first segment, time taken = $$\frac{d}{10}$$ hours

For the second segment, time taken = $$\frac{d}{20}$$ hours

For the third segment, time taken = $$\frac{d}{60}$$ hours

Total time taken = $$\frac{d}{10}$$ + $$\frac{d}{20}$$ + $$\frac{d}{60}$$ = $$\frac{d}{6}$$ hours.

Now, we know that Average Speed = $$\frac{Total Distance Travelled }{ Total time taken}$$.

Substituting the relevant values, we have,
Average speed = $$\frac{3d }{ (d/6)}$$ = 18kmph.

The correct answer option is A.

Hope that helps!
_________________ Re: A car travels the first one-third of a certain distance with a speed   [#permalink] 10 Jan 2020, 01:40
Display posts from previous: Sort by

# A car travels the first one-third of a certain distance with a speed  