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

It is currently 21 Feb 2019, 22:28

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

Two persons start walking on a road that diverge at an angle of 120°.

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

Hide Tags

 
Manager
Manager
User avatar
G
Joined: 01 Jun 2015
Posts: 215
Location: India
Concentration: Strategy, International Business
GMAT 1: 620 Q48 V26
GMAT ToolKit User
Two persons start walking on a road that diverge at an angle of 120°.  [#permalink]

Show Tags

New post Updated on: 24 Oct 2018, 02:18
8
00:00
A
B
C
D
E

Difficulty:

  55% (hard)

Question Stats:

67% (02:53) correct 33% (02:40) wrong based on 85 sessions

HideShow timer Statistics

Image
Two persons start walking on a road that diverge at an angle of 120°. If they walk at the rate of 3 km/h and 2 km/h respectively. Find the distance between them after 4 hours.

A. 5
B. 4√19
C. 7
D. 8√19
E. √19

Attachment:
2018-10-24_1415.png
2018-10-24_1415.png [ 11.16 KiB | Viewed 756 times ]

Originally posted by techiesam on 12 May 2016, 04:01.
Last edited by Bunuel on 24 Oct 2018, 02:18, edited 1 time in total.
Renamed the topic and edited the question.
Most Helpful Expert Reply
Math Expert
User avatar
V
Joined: 02 Aug 2009
Posts: 7334
Premium Member Reviews Badge
Re: Two persons start walking on a road that diverge at an angle of 120°.  [#permalink]

Show Tags

New post 12 May 2016, 05:37
2
ronny123 wrote:
chetan2u wrote:
techiesam wrote:
Two person start walking on a road that diverge at angle of 120 degree.If they walk at the rate of 2kmph and 3 3kmph relatively, then find the distance between them after 4 hours or find the value of c as given in the image attached below.

A.5
B. 4√19
C.7
D. 8√19
E. √19


hi,

Trignometry is NOT tested in GMAT so there has to be another solution..
SEE att image..
Draw an altitude from A to BC extende at D..
Triangle ACD is a right angle triangle, whose HYP is 2*4..
rest sides are CD-4, opp 30 degree and AD - \(4\sqrt{3}\), opp 60 degree..


Now take ADB..
c is hyp..
BD = 3*4 + 4 = 16 and AD = \(4\sqrt{3}\)..
HYp = AC = \(\sqrt{16^2+(4*Sq Root 3})^2\) = \(\sqrt{304}\) = \(4\sqrt{19}\)
B


hi,

Don't be offended but isn't the maths inherent to subject correct ?

if you use c^2 = a^2 + b^2 - 2abcos(120)
= a^2 + b^2 - 2ab(-1/2)
= a^2 + b^2 + ab

a = 2 x 4 = 8
b = 3 x 4 = 12
Putting these values,
c^2 = 8^2 + 12^2 + (8)(12)
= 64 +144 + 96
= 304
c = 4√‾19

Saying Trigo isn't tested on the GMAT isn't changing the solution, my friend
Again, no offense meant.



Hi,
It is not meant for you ..
It is for people who are preparing for GMAT so that they do not get into the area where it is NOT required..
You are most welcome to learn anything being tested or not,
BUT people who are interested in just GMAT should not go away with thought that they have to do trignometry to do this Q..

I don't require to take offence or offend you, I am giving the WAY one should think about this solution
_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html
4) Base while finding % increase and % decrease : https://gmatclub.com/forum/percentage-increase-decrease-what-should-be-the-denominator-287528.html


GMAT Expert

Math Expert
User avatar
V
Joined: 02 Aug 2009
Posts: 7334
Premium Member Reviews Badge
Re: Two persons start walking on a road that diverge at an angle of 120°.  [#permalink]

Show Tags

New post 12 May 2016, 05:16
1
1
techiesam wrote:
Two person start walking on a road that diverge at angle of 120 degree.If they walk at the rate of 2kmph and 3 3kmph relatively, then find the distance between them after 4 hours or find the value of c as given in the image attached below.

A.5
B. 4√19
C.7
D. 8√19
E. √19


hi,

Trignometry is NOT tested in GMAT so there has to be another solution..
SEE att image..
Draw an altitude from A to BC extende at D..
Triangle ACD is a right angle triangle, whose HYP is 2*4..
rest sides are CD-4, opp 30 degree and AD - \(4\sqrt{3}\), opp 60 degree..


Now take ADB..
c is hyp..
BD = 3*4 + 4 = 16 and AD = \(4\sqrt{3}\)..
HYp = AC = \(\sqrt{16^2+(4*Sq Root 3})^2\) = \(\sqrt{304}\) = \(4\sqrt{19}\)
B
Attachments

IMG_5618.JPG
IMG_5618.JPG [ 1.75 MiB | Viewed 2194 times ]


_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html
4) Base while finding % increase and % decrease : https://gmatclub.com/forum/percentage-increase-decrease-what-should-be-the-denominator-287528.html


GMAT Expert

General Discussion
Manager
Manager
avatar
Joined: 12 Jun 2015
Posts: 79
Reviews Badge
Re: Two persons start walking on a road that diverge at an angle of 120°.  [#permalink]

Show Tags

New post Updated on: 12 May 2016, 05:32
hi techiesam,

can you please check if the question is correct, specifically whether one of the speeds is 3 kmph or 33 kmph
Also,
you can simply use the following formula for cos x to get your answer :

c^2 = a^2 + b^2 - 2abcos(120)
= a^2 + b^2 - 2ab(-1/2)
= a^2 + b^2 + ab

Originally posted by ronny123 on 12 May 2016, 04:52.
Last edited by ronny123 on 12 May 2016, 05:32, edited 1 time in total.
Manager
Manager
avatar
Joined: 12 Jun 2015
Posts: 79
Reviews Badge
Re: Two persons start walking on a road that diverge at an angle of 120°.  [#permalink]

Show Tags

New post 12 May 2016, 05:31
chetan2u wrote:
techiesam wrote:
Two person start walking on a road that diverge at angle of 120 degree.If they walk at the rate of 2kmph and 3 3kmph relatively, then find the distance between them after 4 hours or find the value of c as given in the image attached below.

A.5
B. 4√19
C.7
D. 8√19
E. √19


hi,

Trignometry is NOT tested in GMAT so there has to be another solution..
SEE att image..
Draw an altitude from A to BC extende at D..
Triangle ACD is a right angle triangle, whose HYP is 2*4..
rest sides are CD-4, opp 30 degree and AD - \(4\sqrt{3}\), opp 60 degree..


Now take ADB..
c is hyp..
BD = 3*4 + 4 = 16 and AD = \(4\sqrt{3}\)..
HYp = AC = \(\sqrt{16^2+(4*Sq Root 3})^2\) = \(\sqrt{304}\) = \(4\sqrt{19}\)
B


hi,

Don't be offended but isn't the maths inherent to subject correct ?

if you use c^2 = a^2 + b^2 - 2abcos(120)
= a^2 + b^2 - 2ab(-1/2)
= a^2 + b^2 + ab

a = 2 x 4 = 8
b = 3 x 4 = 12
Putting these values,
c^2 = 8^2 + 12^2 + (8)(12)
= 64 +144 + 96
= 304
c = 4√‾19

Saying Trigo isn't tested on the GMAT isn't changing the solution, my friend
Again, no offense meant.
Director
Director
User avatar
D
Joined: 27 May 2012
Posts: 683
Premium Member
Re: Two persons start walking on a road that diverge at an angle of 120°.  [#permalink]

Show Tags

New post 19 Oct 2018, 05:31
1
techiesam wrote:
Two person start walking on a road that diverge at angle of 120 degree.If they walk at the rate of 2kmph and 3 3kmph relatively, then find the distance between them after 4 hours or find the value of c as given in the image attached below.

A.5
B. 4√19
C.7
D. 8√19
E. √19


Dear Moderator,
There is a typo in this question, the latter speed seems to be 3 kmph rather than 33 kmph, hope you will do the needful. Thank you.
_________________

- Stne

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 53066
Re: Two persons start walking on a road that diverge at an angle of 120°.  [#permalink]

Show Tags

New post 24 Oct 2018, 02:19
stne wrote:
techiesam wrote:
Two person start walking on a road that diverge at angle of 120 degree.If they walk at the rate of 2kmph and 3 3kmph relatively, then find the distance between them after 4 hours or find the value of c as given in the image attached below.

A.5
B. 4√19
C.7
D. 8√19
E. √19


Dear Moderator,
There is a typo in this question, the latter speed seems to be 3 kmph rather than 33 kmph, hope you will do the needful. Thank you.


________________
Edited. Thank you.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Manager
Manager
User avatar
G
Joined: 21 Jun 2017
Posts: 234
Concentration: Finance, Economics
WE: Corporate Finance (Commercial Banking)
CAT Tests
Re: Two persons start walking on a road that diverge at an angle of 120°.  [#permalink]

Show Tags

New post 24 Oct 2018, 05:07
Longest side will be opposite to angle C. This means c should be more than 12.
Also by triangle property
4<c<20
Combining,
12<c<20.
By POE answer is B.
PS: sqrt 19 is almost 4.5

Posted from my mobile device
_________________

Even if it takes me 30 attempts, I am determined enough to score 740+ in my 31st attempt. This is it, this is what I have been waiting for, now is the time to get up and fight, for my life is 100% my responsibility.

Dil ye Ziddi hai !!!

GMAT Club Bot
Re: Two persons start walking on a road that diverge at an angle of 120°.   [#permalink] 24 Oct 2018, 05:07
Display posts from previous: Sort by

Two persons start walking on a road that diverge at an angle of 120°.

  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®.