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

It is currently 24 Jun 2018, 18:58

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

Events & Promotions in June
Open Detailed Calendar

How many different handshakes are possible if six girls

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

Hide Tags

2 KUDOS received
Manager
Manager
avatar
Joined: 12 Oct 2011
Posts: 121
GMAT 1: 700 Q48 V37
GMAT 2: 720 Q48 V40
How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 01 Apr 2012, 04:15
2
10
00:00
A
B
C
D
E

Difficulty:

  55% (hard)

Question Stats:

61% (01:06) correct 39% (01:15) wrong based on 444 sessions

HideShow timer Statistics

How many different handshakes are possible if six girls are standing on a circle and each girl shakes hands with every other girl except the two girls standing next to her?

(A) 12
(B) 11
(C) 10
(D) 9
(E) 8

Had to count the scenarios, how can you calculte this with combinatorics?
Expert Post
2 KUDOS received
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 46319
Re: How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 01 Apr 2012, 04:27
2
8
BN1989 wrote:
How many different handshakes are possible if six girls are standing on a circle and each girl shakes hands with every other girl except the two girls standing next to her?

(A) 12
(B) 11
(C) 10
(D) 9
(E) 8

Had to count the scenarios, how can you calculte this with combinatorics?


Each girl in a circle shakes hands with 3 other girls (6 minus herself and the two girls standing next to her): 3*6=18, but since this number counts twice one handshake per pair then # handshakes possible is 18/2=9.

Answer: D.
_________________

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

10 KUDOS received
Manager
Manager
User avatar
Joined: 24 Mar 2010
Posts: 70
Re: How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 24 Dec 2012, 01:39
10
3
Well, I picked a weird way to do this but well it was a short approach

I thought of the girls as sides of a polygon, and a handshake as a diagonal.

Number of diagonal in a n-sided polygon is n(n-3)/2

Number of handshakes -> 6(3)/2 = 9

Hence D.


P.S.
Look what GMAT does to you, m picturing girls as "sides of a polygon"!!...Sigh...
_________________

- Stay Hungry, stay Foolish -

Manager
Manager
avatar
Joined: 24 Oct 2012
Posts: 65
WE: Information Technology (Computer Software)
Re: How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 17 Jun 2014, 07:27
Hi
I am looking for some sample questions to test my arithmatic section, Can you tell me where are these questions from? where are these sub-600, 600 to 700 questions?
thanks
Expert Post
1 KUDOS received
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 46319
Re: How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 17 Jun 2014, 07:43
1
4
GMatAspirerCA wrote:
Hi
I am looking for some sample questions to test my arithmatic section, Can you tell me where are these questions from? where are these sub-600, 600 to 700 questions?
thanks


Check this first:

ALL YOU NEED FOR QUANT



Our questions banks: viewforumtags.php From there:
DS questions on Arithmetic: search.php?search_id=tag&tag_id=30
PS questions on Arithmetic: search.php?search_id=tag&tag_id=51

GMAT PS Question Directory by Topic & Difficulty: gmat-ps-question-directory-by-topic-difficulty-127957.html
GMAT DS Question Directory by Topic & Difficulty: ds-question-directory-by-topic-difficulty-128728.html

100 Hardest Data Sufficiency Questions: 100-hardest-data-sufficiency-questions-162413.html
100 Hardest Problem Solving Questions: 100-hardest-problem-solving-questions-162616.html

Hope this helps.
_________________

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
avatar
Joined: 24 Oct 2012
Posts: 65
WE: Information Technology (Computer Software)
Re: How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 17 Jun 2014, 22:35
Thanks Bunuel, your signature gives good links. thanks for that.
Intern
Intern
User avatar
Joined: 25 Jun 2014
Posts: 40
Re: How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 19 Nov 2014, 10:05
eaakbari wrote:
Well, I picked a weird way to do this but well it was a short approach

I thought of the girls as sides of a polygon, and a handshake as a diagonal.

Number of diagonal in a n-sided polygon is n(n-3)/2

Number of handshakes -> 6(3)/2 = 9

Hence D.


P.S.
Look what GMAT does to you, m picturing girls as "sides of a polygon"!!...Sigh...


I like ur approach and this is funny lol: Look what GMAT does to you, m picturing girls as "sides of a polygon"!!...Sigh...[/quote]
Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 46319
Re: How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 20 Nov 2014, 07:39
eaakbari wrote:
Well, I picked a weird way to do this but well it was a short approach

I thought of the girls as sides of a polygon, and a handshake as a diagonal.

Number of diagonal in a n-sided polygon is n(n-3)/2

Number of handshakes -> 6(3)/2 = 9

Hence D.


P.S.
Look what GMAT does to you, m picturing girls as "sides of a polygon"!!...Sigh...

________________

:-D :-D :-D
_________________

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

1 KUDOS received
VP
VP
avatar
G
Joined: 07 Dec 2014
Posts: 1020
How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 04 Mar 2016, 19:18
1
let n=6
if each of the 6 girls shook hands with each of the other 5, there would be (n)(n-1)/2=15 total handshakes
because each of the 6 shakes hands with only 3 other girls, there are only (3/5)(15)=9 total handshakes
Senior Manager
Senior Manager
avatar
B
Joined: 05 Jan 2017
Posts: 427
Location: India
Premium Member
Re: How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 17 Mar 2017, 01:52
this case is similar to find the number of diagonals = 6C1 x 3C1/2 = 9. ANSWER
Intern
Intern
avatar
B
Joined: 21 Sep 2016
Posts: 29
Re: How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 13 Aug 2017, 01:20
Don't know whether I'm right, or wrong, but I solved this this way: 6C2 - 4C2.
Senior Manager
Senior Manager
avatar
S
Joined: 15 Jan 2017
Posts: 360
CAT Tests
Re: How many different handshakes are possible if six girls [#permalink]

Show Tags

New post 18 Aug 2017, 23:33
eaakbari wrote:
Well, I picked a weird way to do this but well it was a short approach

I thought of the girls as sides of a polygon, and a handshake as a diagonal.

Number of diagonal in a n-sided polygon is n(n-3)/2

Number of handshakes -> 6(3)/2 = 9

Hence D.


P.S.
Look what GMAT does to you, m picturing girls as "sides of a polygon"!!...Sigh...



i will surely use this method for the circular/ 'standing in circle' and condition questions. Pretty insightful, thank you!
Re: How many different handshakes are possible if six girls   [#permalink] 18 Aug 2017, 23:33
Display posts from previous: Sort by

How many different handshakes are possible if six girls

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


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®.