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 350,000 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:

Sorry for posting this, it may sound silly to someone, but I have problem understanding the question:

How many integers n are there such that r < n < s? (1) s - r = 5 (2) r and s are not integers.

My solution: For (1), whether r and s are integer or not, there can be so many "groups" of 4 or 5 n that fit the conditions.

So (1) not enough and (2) not enough, apparently (1) and (2) not enough, according to my "reasoning" above.

So I chose E Please comment, thanks

The question is: how many integers \(n\) satisfy \(r < n < s\), or how many integers are between \(r\) and \(s\), not inclusive?

Note that if \(r\) and \(s\) are integers, for example \(s=5\) and \(r=0\) then there will be 4 integers between them: 1, 2, 3, and 4. But if \(r\) and \(s\) are NOT integers for example \(s=5.5\) and \(r=0.5\) then there will be 5, so one more, integers between them: 1, 2, 3, 4 and 5.

The "number" of n can be multiple of 4 or 5, says 8 or 10, 12, 15, ... can not be determined...

It seems that you misinterpreted the question.

Question ask about the number of integers between r and s, not inclusive.

For example: how many integers are between 10 and 15, not inclusive? Answer: 4, namely 11, 12, 13, and 14. Or: how many integers are between 5.3 and 10.3? Answer: 5, namely 5, 6, 7, 8, 9 and 10.

So taken together statements are sufficient to answer that there are 5 integers between r and s.

this is one of the trickiest questions I have ever seen so far - in test conditions - time and pressure, I am not going to consider C as an option EVER, since there are 5 values for n ... but it is actually that 5 is what the question is looking for ... tough one

Re: How many integers n are there such that r < n< 5 ? [#permalink]
22 Apr 2012, 12:44

1

This post received KUDOS

Expert's post

1

This post was BOOKMARKED

How many integers n are there such that r < n< s ?

The question asks: how many integers \(n\) satisfy \(r < n < s\), or how many integers are between \(r\) and \(s\), not inclusive?

Notice that if \(r\) and \(s\) are integers, for example \(s=5\) and \(r=0\) then there will be 4 integers between them: 1, 2, 3, and 4. But if \(r\) and \(s\) are NOT integers for example \(s=5.5\) and \(r=0.5\) then there will be 5, so one more, integers between them: 1, 2, 3, 4 and 5.

(1) s - r = 5. Not sufficient. (2) r and s are not integers. Not sufficient.

(1)+(2) According to above reasoning since r and s are not integers then there are 5 integers between them (case 2). Sufficient.

Re: How many integers n are there such that r < n< s ? [#permalink]
22 Apr 2012, 13:00

Thanks for putting this together. I received a 29 on my last math section of the GMAT. Any suggestions for improvement since I take it again on May 31st? Why did you choose that picture? I like it and have not seen anything similar to it.

Re: How many integers n are there such that r < n< 5 ? [#permalink]
22 Apr 2012, 13:09

Expert's post

Bunuel wrote:

How many integers n are there such that r < n< s ?

The question asks: how many integers \(n\) satisfy \(r < n < s\), or how many integers are between \(r\) and \(s\), not inclusive?

Notice that if \(r\) and \(s\) are integers, for example \(s=5\) and \(r=0\) then there will be 4 integers between them: 1, 2, 3, and 4. But if \(r\) and \(s\) are NOT integers for example \(s=5.5\) and \(r=0.5\) then there will be 5, so one more, integers between them: 1, 2, 3, 4 and 5.

(1) s - r = 5. Not sufficient. (2) r and s are not integers. Not sufficient.

(1)+(2) According to above reasoning since r and s are not integers then there are 5 integers between them (case 2). Sufficient.

Answer: C.

Hope it's clear.

can you please eleborate the concept behind this ?? indeed is true but I didn't notice this before.

Re: How many integers n are there such that r < n< 5 ? [#permalink]
22 Apr 2012, 13:15

Expert's post

carcass wrote:

Bunuel wrote:

How many integers n are there such that r < n< s ?

The question asks: how many integers \(n\) satisfy \(r < n < s\), or how many integers are between \(r\) and \(s\), not inclusive?

Notice that if \(r\) and \(s\) are integers, for example \(s=5\) and \(r=0\) then there will be 4 integers between them: 1, 2, 3, and 4. But if \(r\) and \(s\) are NOT integers for example \(s=5.5\) and \(r=0.5\) then there will be 5, so one more, integers between them: 1, 2, 3, 4 and 5.

(1) s - r = 5. Not sufficient. (2) r and s are not integers. Not sufficient.

(1)+(2) According to above reasoning since r and s are not integers then there are 5 integers between them (case 2). Sufficient.

Answer: C.

Hope it's clear.

can you please eleborate the concept behind this ?? indeed is true but I didn't notice this before.

Thanks

There isn't some special concept behind it. It's just common sense based on observation. _________________

Re: How many integers n are there such that r < n < s? [#permalink]
30 Dec 2012, 18:50

hmm... I chose E with the reasoning that the question does not mention that the integers are consecutive. There could be duplicate integers between r and s such that r=0 and s=5 and values of n to be 1, 1, 2, 3, 4, 4.

Re: How many integers n are there such that r < n < s? [#permalink]
31 Dec 2012, 02:22

Expert's post

4sguy wrote:

hmm... I chose E with the reasoning that the question does not mention that the integers are consecutive. There could be duplicate integers between r and s such that r=0 and s=5 and values of n to be 1, 1, 2, 3, 4, 4.

Re: How many integers n are there such that r < n < s? [#permalink]
18 Jun 2013, 19:35

I had and still continue to have trouble interpreting this question.

how many integers n are there such that r<n<s r and s are 0 or 5 -> n can be 1,2,3,4 r and s are 110 or 115-> n can be another set of 4 no.s

i thought n can have any number of infinite values for r-s=5 or for r and s are not integers.....can some one pls make it clear...

i understand some of the explanations are towards n=no. of integers between two given values, but question ask how many integers n are there that meet the criteria...

Re: How many integers n are there such that r < n < s? [#permalink]
19 Jun 2013, 01:36

1

This post received KUDOS

Expert's post

nanz236 wrote:

I had and still continue to have trouble interpreting this question.

how many integers n are there such that r<n<s r and s are 0 or 5 -> n can be 1,2,3,4 r and s are 110 or 115-> n can be another set of 4 no.s

i thought n can have any number of infinite values for r-s=5 or for r and s are not integers.....can some one pls make it clear...

i understand some of the explanations are towards n=no. of integers between two given values, but question ask how many integers n are there that meet the criteria...

How many integers n are there such that 0 < n < 5? Answer: 4. How many integers n are there such that 110 < n < 115? Answer: 4.

Re: How many integers n are there such that r < n< s ? [#permalink]
18 May 2014, 09:46

1

This post received KUDOS

if we knew about s and r (integers or not integers) our task would be simplified to st(1) Suff. Since we know nothing about s and r, there could be always four integers (case when s and r are integers) or five integers (when s or r is not integer)

st(2) helps with assigning type for our numbers (s and r), but we know nothing about values

combined st(1&2) supports our previously inquired data, i.e. s and r are not integers, hence the number of integers in the given interval will always be 5.

Re: How many integers n are there such that r < n < s? [#permalink]
05 Dec 2014, 20:35

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. _________________

Harvard asks you to write a post interview reflection (PIR) within 24 hours of your interview. Many have said that there is little you can do in this...