It is currently 21 Oct 2017, 18:40

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# Is s an odd integer?

Author Message
TAGS:

### Hide Tags

Intern
Joined: 12 Dec 2010
Posts: 14

Kudos [?]: 31 [1], given: 0

Schools: Wharton, Columbia, Booth, NYU
Is s an odd integer? [#permalink]

### Show Tags

19 Dec 2010, 19:45
1
KUDOS
3
This post was
BOOKMARKED
00:00

Difficulty:

35% (medium)

Question Stats:

61% (01:01) correct 39% (00:46) wrong based on 270 sessions

### HideShow timer Statistics

Is s an odd integer?

(1) $$\sqrt{s}$$ is not an even integer.
(2) s^2 is not an even integer.

When not mentioned do we consider irrational numbers as well? Please clarify. Thanks !
[Reveal] Spoiler: OA

_________________

Practice, More Practice, Still More Practice... THE only way to succeed!!!
+1Kudos, if this helps with your preparation. Good luck!

Kudos [?]: 31 [1], given: 0

Math Expert
Joined: 02 Sep 2009
Posts: 41892

Kudos [?]: 129174 [0], given: 12194

Re: ODD vs EVEN Trick Question? [#permalink]

### Show Tags

20 Dec 2010, 00:38
Expert's post
6
This post was
BOOKMARKED
MasterGMAT12 wrote:

Is s an odd integer?
(1) sqrt(s) is not an even integer.
(2) s^2 is not an even integer.

GMAT is dealing only with Real Numbers: Integers, Fractions and Irrational Numbers. So, if there is no restriction then you must consider irrational numbers as well.

Note that only integers can be even or odd. So, for example there is no difference in asking "is s an odd integer" and "is s odd".

For more check Number Theory chapter of Math Book: math-number-theory-88376.html

Back to the original question:

Is s an odd integer?

(1) sqrt(s) is not an even integer --> $$\sqrt{s}$$ might be an odd integer, for example 1, 3, ... and in this case $$s$$ will be an odd integer, but $$\sqrt{s}$$ might as well be a fraction, for example 1/3, 7/5 and in this case $$s$$ won't be an integer at all. $$s$$ also might be an irrational number, for example $$\sqrt{2}$$, $$\sqrt{3}$$, $$\sqrt{{\frac{1}{3}}}$$ ... and in this case $$s$$ might or might not be an odd integer. Not sufficient.

(2) s^2 is not an even integer --> the same here: $$s^2$$ might be a square of an odd integer, for example 1, 9, ... and in this case $$s$$ will be an odd integer, but $$s^2$$ might as well not be a perfect square, for example 1/3, 17, and in this case $$s$$ won't be an integer at all. Not sufficient.

(1)+(2) When combined still insufficient: if $$s=1$$ then the answer will be YES but if if $$s=\frac{1}{3}$$ then the answer will be NO.

Hope it's clear.
_________________

Kudos [?]: 129174 [0], given: 12194

Manager
Affiliations: Project Management Professional (PMP)
Joined: 30 Jun 2011
Posts: 198

Kudos [?]: 83 [0], given: 12

Location: New Delhi, India
Re: ODD vs EVEN Trick Question? [#permalink]

### Show Tags

02 Jul 2012, 02:44
Bunuel wrote:
MasterGMAT12 wrote:

Is s an odd integer?
(1) sqrt(s) is not an even integer.
(2) s^2 is not an even integer.

GMAT is dealing only with Real Numbers: Integers, Fractions and Irrational Numbers. So, if there is no restriction then you must consider irrational numbers as well.

Note that only integers can be even or odd. So, for example there is no difference in asking "is s an odd integer" and "is s odd".

For more check Number Theory chapter of Math Book: math-number-theory-88376.html

Back to the original question:

Is s an odd integer?

(1) sqrt(s) is not an even integer --> $$\sqrt{s}$$ might be an odd integer, for example 1, 3, ... and in this case $$s$$ will be an odd integer, but $$\sqrt{s}$$ might as well be a fraction, for example 1/3, 7/5 and in this case $$s$$ won't be an integer at all. $$s$$ also might be an irrational number, for example $$\sqrt{2}$$, $$\sqrt{3}$$, $$\sqrt{{\frac{1}{3}}}$$ ... and in this case $$s$$ might or might not be an odd integer. Not sufficient.

(2) s^2 is not an even integer --> the same here: $$s^2$$ might be a square of an odd integer, for example 1, 9, ... and in this case $$s$$ will be an odd integer, but $$s^2$$ might as well not be a perfect square, for example 1/3, 17, and in this case $$s$$ won't be an integer at all. Not sufficient.

(1)+(2) When combined still insufficient: if $$s=1$$ then the answer will be YES but if if $$s=\frac{1}{3}$$ then the answer will be NO.

Hope it's clear.

Dear Bunuel

Can you please elaborate a bit further... not clear with the explanation.
_________________

Best
Vaibhav

If you found my contribution helpful, please click the +1 Kudos button on the left, Thanks

Kudos [?]: 83 [0], given: 12

Math Expert
Joined: 02 Sep 2009
Posts: 41892

Kudos [?]: 129174 [0], given: 12194

Re: ODD vs EVEN Trick Question? [#permalink]

### Show Tags

02 Jul 2012, 02:47
narangvaibhav wrote:
Can you please elaborate a bit further... not clear with the explanation.

Can you please tell what exactly didn't you understand?
_________________

Kudos [?]: 129174 [0], given: 12194

Manager
Affiliations: Project Management Professional (PMP)
Joined: 30 Jun 2011
Posts: 198

Kudos [?]: 83 [0], given: 12

Location: New Delhi, India
Re: ODD vs EVEN Trick Question? [#permalink]

### Show Tags

03 Jul 2012, 07:47
Bunuel wrote:
narangvaibhav wrote:
Can you please elaborate a bit further... not clear with the explanation.

Can you please tell what exactly didn't you understand?

Couldn't get why option1 and 2 together are not sufficient

Posted from my mobile device
_________________

Best
Vaibhav

If you found my contribution helpful, please click the +1 Kudos button on the left, Thanks

Kudos [?]: 83 [0], given: 12

Math Expert
Joined: 02 Sep 2009
Posts: 41892

Kudos [?]: 129174 [0], given: 12194

Re: ODD vs EVEN Trick Question? [#permalink]

### Show Tags

03 Jul 2012, 07:50
narangvaibhav wrote:
Bunuel wrote:
narangvaibhav wrote:
Can you please elaborate a bit further... not clear with the explanation.

Can you please tell what exactly didn't you understand?

Couldn't get why option1 and 2 together are not sufficient

Posted from my mobile device

It's explained in the solution.

Consider two cases: if $$s=1$$ then the answer will be YES but if if $$s=\frac{1}{3}$$ then the answer will be NO.
_________________

Kudos [?]: 129174 [0], given: 12194

GMAT Club Legend
Joined: 09 Sep 2013
Posts: 16587

Kudos [?]: 273 [0], given: 0

Re: Is s an odd integer? [#permalink]

### Show Tags

29 Jul 2014, 20:58
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.
_________________

Kudos [?]: 273 [0], given: 0

GMAT Club Legend
Joined: 09 Sep 2013
Posts: 16587

Kudos [?]: 273 [0], given: 0

Re: Is s an odd integer? [#permalink]

### Show Tags

27 Sep 2015, 09:14
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.
_________________

Kudos [?]: 273 [0], given: 0

GMAT Club Legend
Joined: 09 Sep 2013
Posts: 16587

Kudos [?]: 273 [0], given: 0

Re: Is s an odd integer? [#permalink]

### Show Tags

23 Dec 2016, 09:38
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.
_________________

Kudos [?]: 273 [0], given: 0

Re: Is s an odd integer?   [#permalink] 23 Dec 2016, 09:38
Display posts from previous: Sort by