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.

It appears that you are browsing the GMAT Club forum unregistered!

Signing up is free, quick, and confidential.
Join other 500,000 members and get the full benefits of GMAT Club

Registration gives you:

Tests

Take 11 tests and quizzes from GMAT Club and leading GMAT prep companies such as Manhattan GMAT,
Knewton, and others. All are free for GMAT Club members.

Applicant Stats

View detailed applicant stats such as GPA, GMAT score, work experience, location, application
status, and more

Books/Downloads

Download thousands of study notes,
question collections, GMAT Club’s
Grammar and Math books.
All are free!

Thank you for using the timer!
We noticed you are actually not timing your practice. Click the START button first next time you use the timer.
There are many benefits to timing your practice, including:

Re: The set S has 36 different subsets each of which contains [#permalink]

Show Tags

21 Aug 2014, 13:38

The Set S has "n" elements {x1,x1,...,xn}

Out of these "n" elements if we try to make subset of two element each then we can make 36 such subsets, which are correctly denoted by you as (a1,b1),(a2,b2),(a3,b3),(a4,b4)...............(a36,b36) So, S' = (a1,b1),(a2,b2),(a3,b3),(a4,b4)...............(a36,b36) (Note a ' after S in previous line)

Now, to find out the number of elements in the set S we are given by we can make 36 subsets of two elements each, So number of subsets of two element each which can be formed from a Set S which has n elements = nC2

read the second half of the question which says "How many subsets of S could contain exactly three elements each" So, S is the set of "n" elements and not the Set of subsets of two elements

Hope it helps!

paandey wrote:

Why nc2 = 36 ?

What I understand from question is that s = ((a1,b1),(a2,b2),(a3,b3),(a4,b4)...............(a36,b36))

Is this wrong understanding of question ? Kindly help

Re: The set S has 36 different subsets each of which contains [#permalink]

Show Tags

15 Oct 2017, 04:27

Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________