It is currently 17 Nov 2018, 04:40
My Tests

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.

There are X people at a dance, where X is an integer

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Moderator
Moderator
User avatar
Joined: 18 Apr 2015
Posts: 4895
Followers: 74

Kudos [?]: 976 [0], given: 4494

CAT Tests
There are X people at a dance, where X is an integer [#permalink] New post 09 May 2018, 09:13
Expert's post
00:00

Question Stats:

0% (00:00) correct 100% (00:00) wrong based on 5 sessions
There are \(X\) people at a dance, where \(X\) is an integer greater than 1. The number of different pairs of people who can be partnered up for the waltz is \(Z\). Which of the following could be the value of \(Z\) ?

A. 2

B. 6

C. 9

D. 14

E. 20
[Reveal] Spoiler: OA

_________________

Get the 2 FREE GREPrepclub Tests

Manager
Manager
Joined: 27 Feb 2017
Posts: 150
Followers: 0

Kudos [?]: 40 [0], given: 15

Re: There are people at a dance, where is an integer greater tha [#permalink] New post 09 May 2018, 13:22
someone please explain?
1 KUDOS received
Director
Director
User avatar
Joined: 07 Jan 2018
Posts: 538
Followers: 4

Kudos [?]: 464 [1] , given: 82

CAT Tests
Re: There are X people at a dance, where X is an integer [#permalink] New post 10 May 2018, 03:15
1
This post received
KUDOS
A pair of people is required. Z is the number of unique pair of people for the dance
number of total people \(> 1\)
Let us start with two people

There are two spots in a pair
Here we chose \(2\) people out of 2 people Hence \(2c2\) \(= 1\). Not in the option

Let us try \(3\)
\(3c2 = 3\). Not in the option

Let us try \(4\)
\(4c2 = 6\). This is the correct option
B
_________________

This is my response to the question and may be incorrect. Feel free to rectify any mistakes

Manager
Manager
Joined: 27 Feb 2017
Posts: 150
Followers: 0

Kudos [?]: 40 [0], given: 15

Re: There are X people at a dance, where X is an integer [#permalink] New post 11 May 2018, 13:08
amorphous wrote:
A pair of people is required. Z is the number of unique pair of people for the dance
number of total people \(> 1\)
Let us start with two people

There are two spots in a pair
Here we chose \(2\) people out of 2 people Hence \(2c2\) \(= 1\). Not in the option

Let us try \(3\)
\(3c2 = 3\). Not in the option

Let us try \(4\)
\(4c2 = 6\). This is the correct option
B


so how did we eliminate the other options? And is there an easier and quicker way to do this rather than trial and error? I also had a hard time understanding the wording of the question
1 KUDOS received
Director
Director
User avatar
Joined: 07 Jan 2018
Posts: 538
Followers: 4

Kudos [?]: 464 [1] , given: 82

CAT Tests
Re: There are X people at a dance, where X is an integer [#permalink] New post 11 May 2018, 19:49
1
This post received
KUDOS
Since this is a select one multiple choice ans there cannot be more than 1 ans choice. If in the process of solving the problem we get our ans, no need to work with other options.
There can be other methods for solving the ans for eg. you can formulate a eqn \(x(x-1) = 2a\); where a is the ans options
make the left side equivalent to the right side for correct ans such as \(x(x-1) = 4*3\) for option B try it with different options only B is correct
Realize that this is not a time consuming question. If you understand the logic the question should not take more than 1'30 min to answer
Wording of questions can be confusing, ets regularly uses this technique to make test-takers chose wrong answers. Get familiar with gre language. Give attention to sign words such as only, not, must be, could be, if, approximately and so on
_________________

This is my response to the question and may be incorrect. Feel free to rectify any mistakes

Re: There are X people at a dance, where X is an integer   [#permalink] 11 May 2018, 19:49
Display posts from previous: Sort by

There are X people at a dance, where X is an integer

  Question banks Downloads My Bookmarks Reviews Important topics  


cron

GRE Prep Club Forum Home| About| Terms and Conditions and Privacy Policy| GRE Prep Club Rules| Contact

Powered by phpBB © phpBB Group

Kindly note that the GRE® test is a registered trademark of the Educational Testing Service®, and this site has neither been reviewed nor endorsed by ETS®.