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

It is currently 21 Feb 2019, 08:43

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
Events & Promotions in February
PrevNext
SuMoTuWeThFrSa
272829303112
3456789
10111213141516
17181920212223
242526272812
Open Detailed Calendar
  • Online GMAT boot camp for FREE

     February 21, 2019

     February 21, 2019

     10:00 PM PST

     11:00 PM PST

    Kick off your 2019 GMAT prep with a free 7-day boot camp that includes free online lessons, webinars, and a full GMAT course access. Limited for the first 99 registrants! Feb. 21st until the 27th.
  • Free GMAT RC Webinar

     February 23, 2019

     February 23, 2019

     07:00 AM PST

     09:00 AM PST

    Learn reading strategies that can help even non-voracious reader to master GMAT RC. Saturday, February 23rd at 7 AM PT

Last weekend, Sid visited his friend Mia who lives at 90 miles from hi

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

Hide Tags

 
Manager
Manager
User avatar
G
Joined: 10 Oct 2018
Posts: 129
Location: United States
GPA: 4
WE: Human Resources (Human Resources)
Last weekend, Sid visited his friend Mia who lives at 90 miles from hi  [#permalink]

Show Tags

New post Updated on: 18 Jan 2019, 08:19
1
00:00
A
B
C
D
E

Difficulty:

  55% (hard)

Question Stats:

69% (03:22) correct 31% (03:31) wrong based on 15 sessions

HideShow timer Statistics

Last weekend, Sid visited his friend Mia who lives at 90 miles from his place. He divided his onward and return journey in different manner. He reached Veronica’s place by dividing the total distance in two equal part, at a speed of 15 mph and 30 mph respectively. He stayed there for 2 hours and took the return journey via the same path by dividing the total journey time in three equal parts, at a speed of 5 mph, 10 mph, and 15 mph respectively. If x, y, and z denote the average speed of his onward, return, and overall journey respectively, what is the value of x + y + z?

A) 10
B) 11.6
C) 16.25
D) 20
E) 41.6

_________________

Kudos OK Please!!


Originally posted by topper97 on 18 Jan 2019, 07:17.
Last edited by topper97 on 18 Jan 2019, 08:19, edited 1 time in total.
Veritas Prep GMAT Instructor
User avatar
D
Joined: 16 Oct 2010
Posts: 8891
Location: Pune, India
Re: Last weekend, Sid visited his friend Mia who lives at 90 miles from hi  [#permalink]

Show Tags

New post 18 Jan 2019, 08:15
topper97 wrote:
Last weekend, Sid visited his friend Mia who lives at 90 miles from his place. He divided his onward and return journey in different manner. He reached Veronica’s place by dividing the total distance in two equal part, at a speed of 15 mph and 30 mph respectively. He stayed there for 2 hours and took the return journey via the same path by dividing the total journey time in three equal parts, at a speed of 5 mph, 10 mph, and 15 mph respectively. If x, y, and z denote the average speed of his onward, return, and overall journey respectively, what is the value of x + y + z?

A) 10
B) 11.6
C) 16.25
D) 20
E) 41.6

Bunuel pls help. Thank-you in advance!


Average speed when equal distances are travelled for onward journey = 2ab/(a + b) = 2*15*30/(15 + 30) = 20 mph

Average speed when time taken is same for return journey = (5 + 10 + 15)/3 = 10 mph

Overall average speed when travelling for same distance (onward and return) = 2ab/(a + b) = 2*20*10/(20 + 10) = 40/3 = 13.33 mph

Sum of all speeds = 20 + 10 + 13.33 = 43.33 mph

Check this post for a discussion of this formula: https://www.veritasprep.com/blog/2015/0 ... -the-gmat/
_________________

Karishma
Veritas Prep GMAT Instructor

Learn more about how Veritas Prep can help you achieve a great GMAT score by checking out their GMAT Prep Options >

Manager
Manager
User avatar
G
Joined: 10 Oct 2018
Posts: 129
Location: United States
GPA: 4
WE: Human Resources (Human Resources)
Last weekend, Sid visited his friend Mia who lives at 90 miles from hi  [#permalink]

Show Tags

New post 18 Jan 2019, 08:36
VeritasKarishma wrote:

Average speed when equal distances are travelled for onward journey = 2ab/(a + b) = 2*15*30/(15 + 30) = 20 mph

Average speed when time taken is same for return journey = (5 + 10 + 15)/3 = 10 mph

Overall average speed when travelling for same distance (onward and return) = 2ab/(a + b) = 2*20*10/(20 + 10) = 40/3 = 13.33 mph

Sum of all speeds = 20 + 10 + 13.33 = 43.33 mph

Check this post for a discussion of this formula: https://www.veritasprep.com/blog/2015/0 ... -the-gmat/


I had doubt from the highlighted part. Generally, outward and return speeds can be different then why did you take the average speed of both to find overall avg speed? Maybe I'm missing something

Also, for return journey, why didn't you use 3abc/(ab + bc + ca) as the total journey time is in three equal parts.
_________________

Kudos OK Please!!

GMAT Club Bot
Last weekend, Sid visited his friend Mia who lives at 90 miles from hi   [#permalink] 18 Jan 2019, 08:36
Display posts from previous: Sort by

Last weekend, Sid visited his friend Mia who lives at 90 miles from hi

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


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

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®.