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: Data sufficiency overlapping sets [#permalink]

Show Tags

12 Apr 2011, 16:02

2

This post received KUDOS

skbjunior wrote:

How many members of a certain country club play both squash and racquetball?

(1) 110 members of the country club play either squash or racquetball.

(2) 70 members of the country club play squash and 65 members of the country club play racquetball.

I will upload OA soon. Thank you for your response.

(1) \(n(R \hspace{2} \cup \hspace{2} S)=110\) Possible that all 110 play both. OR 40 play only racquetball, 40 play only squash and 30 play both. Not Sufficient.

(2) \(n(R)=65\) \(n(S)=70\) Possible that 65 play both games. OR 35 play both games. Not Sufficient.

Re: Data sufficiency overlapping sets [#permalink]

Show Tags

12 Apr 2011, 16:20

fluke wrote:

skbjunior wrote:

How many members of a certain country club play both squash and racquetball?

(1) 110 members of the country club play either squash or racquetball.

(2) 70 members of the country club play squash and 65 members of the country club play racquetball.

I will upload OA soon. Thank you for your response.

(1) \(n(R \hspace{2} \cup \hspace{2} S)=110\) Possible that all 110 play both. OR 40 play only racquetball, 40 play only squash and 30 play both. Not Sufficient.

(2) \(n(R)=65\) \(n(S)=70\) Possible that 65 play both games. OR 35 play both games. Not Sufficient.

Thanks for your response fluke. C is indeed an OA. I chose E though because nowhere it is mentioned that 'all the members play either squash or racquetball' or '0 members play neither squash nor racquetball.' Is my thought-process wrong in this case?

Re: Data sufficiency overlapping sets [#permalink]

Show Tags

12 Apr 2011, 19:14

1

This post received KUDOS

(1) is insufficient as we don't know about the break-up of memebrs who play squash or racquetball

(2) is insufficient as we don't know how many total members are there

Combining (1) and (2)

110 = 70 + 65 - both

=> both = 135 - 110 = 25

Answer - C

@skbjunior 'all the members play either squash or racquetball' means that all the members play at least one of the two sports and a few of them *may* play both the sports.

As a rough example for visualization, If you draw a Venn diagram of two overlapping cirlces inside a rectangle, in this case the area outside of two circles and within the rectangle will be zero.
_________________

Formula of Life -> Achievement/Potential = k * Happiness (where k is a constant)

Re: Data sufficiency overlapping sets [#permalink]

Show Tags

12 Apr 2011, 22:49

skbjunior wrote:

Thanks for your response fluke. C is indeed an OA. I chose E though because nowhere it is mentioned that 'all the members play either squash or racquetball' or '0 members play neither squash nor racquetball.' Is my thought-process wrong in this case?

True. Your thought process is not completely off-track. There could be 1000 members, out of which only 110 play either racquetball or squash.

Note, there are few formulas to find different things:

If you are given total number of members, then you would use the following and here, you would need that extra piece of information that everyone plays either racquetball or squash. \(n(Total \hspace{2} members)=n(R)+n(S)-n(R \hspace{2} \cap \hspace{2} S)+n(Neither)\)

But, if we are not given how many "Total Members" are there, then we would simply use: \(n(R \hspace{2} \cup \hspace{2} S)=n(R)+n(S)-n(R \hspace{2} \cap \hspace{2} S)\) Here, we don't need the total member count or the extra piece of information.
_________________

Re: Data sufficiency overlapping sets [#permalink]

Show Tags

26 Nov 2011, 06:31

fluke wrote:

skbjunior wrote:

Thanks for your response fluke. C is indeed an OA. I chose E though because nowhere it is mentioned that 'all the members play either squash or racquetball' or '0 members play neither squash nor racquetball.' Is my thought-process wrong in this case?

True. Your thought process is not completely off-track. There could be 1000 members, out of which only 110 play either racquetball or squash.

That is correct. Nowhere it is stated because you don't need this information to answer the question.

Note: It is wrong to assume from the first statement that the total number of members is 110 or that members who play neither sport are 0.

Re: How many members of a certain country club play both squash [#permalink]

Show Tags

26 Nov 2011, 09:24

I tried doing it MGMAT way. and keep getting E. Please see the attachment. W/o knowing formula, i ended up using matrix, and having hard time to understand the OA. Can someone please advice/explain a bit more?

Re: How many members of a certain country club play both squash [#permalink]

Show Tags

26 Nov 2011, 10:58

2

This post received KUDOS

BDSunDevil wrote:

I tried doing it MGMAT way. and keep getting E. Please see the attachment. W/o knowing formula, i ended up using matrix, and having hard time to understand the OA. Can someone please advice/explain a bit more?

Matrix Additions/Corrections:

First of all cross out the 110 as total from the matrix. We don't know that. Name the Question Mark (?) in your matrix as \(x\). The box below \(x\) as \(y\) The box on the right of \(x\) as \(z\).

Solution:

From Statement 1 we know that: \(x+y+z=110\) (1)

From the Matrix we can see that \(x+y=70\) (2) and \(x+z=65\) (3)

Re: How many members of a certain country club play both squash [#permalink]

Show Tags

26 Nov 2011, 22:19

I feel that the wording in this question is not very clear. Saying that "110 members of the country club play either squash or racquetball" sounds to my ears like 110 member play one or the other, but not both (this is the normal English meaning of either ... or ...). Is this the wrong way to understand this construction on the GMAT? If so, how would you expect exclusive or to be expressed?

Obviously in this case it means inclusive or because otherwise you seem to end up with 12.5 people playing both sports!

Re: How many members of a certain country club play both squash [#permalink]

Show Tags

27 Nov 2011, 05:08

bobfirth wrote:

I feel that the wording in this question is not very clear. Saying that "110 members of the country club play either squash or racquetball" sounds to my ears like 110 member play one or the other, but not both (this is the normal English meaning of either ... or ...). Is this the wrong way to understand this construction on the GMAT? If so, how would you expect exclusive or to be expressed?

Obviously in this case it means inclusive or because otherwise you seem to end up with 12.5 people playing both sports!

Re: How many members of a certain country club play both squash [#permalink]

Show Tags

29 Nov 2011, 03:18

1

This post received KUDOS

BDSunDevil wrote:

I tried doing it MGMAT way. and keep getting E. Please see the attachment. W/o knowing formula, i ended up using matrix, and having hard time to understand the OA. Can someone please advice/explain a bit more?

your matrix will work as soon as you put 0 in the 'niether squash nor r ball region. This is because the data given is about r ball or squash players....nothing is said about other members of the club. The '110' you have fited in the total bosx is the same 110 members of the country club who play either squash or racquetball. (as given in statement1)

EDIT: i MADE A MISTAKE IN WRITING 35....IT SHOULD BE 45....

Attachments

untitled.jpg [ 12.41 KiB | Viewed 2132 times ]

Last edited by Dreaming on 29 Nov 2011, 05:37, edited 2 times in total.

Re: How many members of a certain country club play both squash [#permalink]

Show Tags

13 Oct 2013, 07:11

1

This post received KUDOS

skbjunior wrote:

How many members of a certain country club play both squash and racquetball?

(1) 110 members of the country club play either squash or racquetball.

(2) 70 members of the country club play squash and 65 members of the country club play racquetball.

Thank you for your response.

I also tried using the Double-set matrix for this one, but in the middle of the problem changed to use the classic formula--> Total = A + B - Both + Neither and realized I had everything. Sometimes, try to visualize the problem in its entirety and don't force a given method. There might be a better way to draw some logic conclusions, or use a backup approach.

Re: How many members of a certain country club play both squash [#permalink]

Show Tags

21 Oct 2016, 00:16

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.
_________________

There’s something in Pacific North West that you cannot find anywhere else. The atmosphere and scenic nature are next to none, with mountains on one side and ocean on...

This month I got selected by Stanford GSB to be included in “Best & Brightest, Class of 2017” by Poets & Quants. Besides feeling honored for being part of...

Joe Navarro is an ex FBI agent who was a founding member of the FBI’s Behavioural Analysis Program. He was a body language expert who he used his ability to successfully...