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

It is currently 07 Dec 2019, 15:43

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

Cars J and K are making the trip from City A to City B. Car J departs

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Find Similar Topics 
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 59588
Cars J and K are making the trip from City A to City B. Car J departs  [#permalink]

Show Tags

New post 13 Nov 2019, 06:05
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

54% (02:04) correct 46% (02:48) wrong based on 59 sessions

HideShow timer Statistics

Cars J and K are making the trip from City A to City B. Car J departs from City A 15 minutes after Car K does, and both cars travel along the same route. If Car K travels at a constant speed that is 80% the constant speed of Car J, then how many minutes will elapse before Car J catches up to Car K?

A. 20
B. 45
C. 60
D. 75
E. 1230


Are You Up For the Challenge: 700 Level Questions

_________________
Manager
Manager
avatar
S
Joined: 10 Dec 2017
Posts: 150
Location: India
CAT Tests
Cars J and K are making the trip from City A to City B. Car J departs  [#permalink]

Show Tags

New post 13 Nov 2019, 06:21
Bunuel wrote:
Cars J and K are making the trip from City A to City B. Car J departs from City A 15 minutes after Car K does, and both cars travel along the same route. If Car K travels at a constant speed that is 80% the constant speed of Car J, then how many minutes will elapse before Car J catches up to Car K?

A. 20
B. 45
C. 60
D. 75
E. 1230


Are You Up For the Challenge: 700 Level Questions

Speed of Car J= X
Speed of Car K=0.8X
distance travelled by Car K in 15 minutes= 15*0.8X
=12X
So Car J will cover this 12X distance relative to Car K in time "t"
speed*time=distance
(X-0.8X)*t=12X
t=60 minutes
C:)
VP
VP
User avatar
V
Joined: 19 Oct 2018
Posts: 1157
Location: India
Premium Member CAT Tests
Re: Cars J and K are making the trip from City A to City B. Car J departs  [#permalink]

Show Tags

New post 13 Nov 2019, 14:19
\(V_J : V_K= 5:4\)

\(T_J : T_K= 4:5\)

\(T_K - T_J=5x - 4x=15\)

\(T_J= 4x= 4*15=60\)

Bunuel wrote:
Cars J and K are making the trip from City A to City B. Car J departs from City A 15 minutes after Car K does, and both cars travel along the same route. If Car K travels at a constant speed that is 80% the constant speed of Car J, then how many minutes will elapse before Car J catches up to Car K?

A. 20
B. 45
C. 60
D. 75
E. 1230


Are You Up For the Challenge: 700 Level Questions
Senior Manager
Senior Manager
User avatar
G
Joined: 21 Jun 2017
Posts: 327
Location: India
Concentration: Finance, Economics
Schools: IIM
GPA: 3
WE: Corporate Finance (Commercial Banking)
CAT Tests
Cars J and K are making the trip from City A to City B. Car J departs  [#permalink]

Show Tags

New post 14 Nov 2019, 23:33
1
Then how many minutes will elapse before Car J catches up to Car K

(t+15)K = (t)J and K=(4/5)*J . Hence t is 60 . But we are asked of elapsed time so add 15 minutes to it. Answer = 60+15 = 75.
Target Test Prep Representative
User avatar
V
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 8622
Location: United States (CA)
Re: Cars J and K are making the trip from City A to City B. Car J departs  [#permalink]

Show Tags

New post 17 Nov 2019, 20:28
Bunuel wrote:
Cars J and K are making the trip from City A to City B. Car J departs from City A 15 minutes after Car K does, and both cars travel along the same route. If Car K travels at a constant speed that is 80% the constant speed of Car J, then how many minutes will elapse before Car J catches up to Car K?

A. 20
B. 45
C. 60
D. 75
E. 1230


Are You Up For the Challenge: 700 Level Questions


Let r = the speed of Car J, so 0.8r = the speed of Car K. Let’s also let t = Car J’s travel time, in hours; this means that (t + ¼) is Car K’s travel time (because 15 minutes = ¼ hour). We can create the equation:

Car K’s distance = Car J’s distance

(0.8r)(t + 1/4) = rt

0.8(t + 0.25) = t

0.8t + 0.2 = t

0.2 = 0.2t

1 = t

Since 1 hour = 60 minutes, choice C is the correct answer.

Answer: C
_________________

Scott Woodbury-Stewart

Founder and CEO

Scott@TargetTestPrep.com
TTP - Target Test Prep Logo
122 Reviews

5-star rated online GMAT quant
self study course

See why Target Test Prep is the top rated GMAT quant course on GMAT Club. Read Our Reviews

If you find one of my posts helpful, please take a moment to click on the "Kudos" button.

Manager
Manager
avatar
B
Joined: 23 Jul 2015
Posts: 79
Re: Cars J and K are making the trip from City A to City B. Car J departs  [#permalink]

Show Tags

New post 17 Nov 2019, 22:15
1
Why isn't the answer 75? Don't have to count the 15 min delay as well?
GMAT Club Bot
Re: Cars J and K are making the trip from City A to City B. Car J departs   [#permalink] 17 Nov 2019, 22:15
Display posts from previous: Sort by

Cars J and K are making the trip from City A to City B. Car J departs

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  





Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne