It is currently 21 Nov 2017, 05:39

### 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

# m04 Q2

Author Message
Manager
Joined: 11 Nov 2008
Posts: 108

Kudos [?]: 10 [1], given: 5

Location: Indonesia
GMAT 1: 720 Q49 V40
GPA: 3.64
WE: Asset Management (Investment Banking)

### Show Tags

09 Dec 2008, 21:07
1
KUDOS
Is integer $$N$$ even?

1. $$N^2 = N$$
2. $$N = N^3$$

[Reveal] Spoiler: OA
E

Source: GMAT Club Tests - hardest GMAT questions

My answer is D but the answer from the system is E, how is this possible?

Both statement will give us 1 or 0 in which neither is even and it's sufficient to answer the problem.

Kudos [?]: 10 [1], given: 5

Intern
Joined: 25 Nov 2008
Posts: 7

Kudos [?]: 10 [2], given: 0

### Show Tags

09 Dec 2008, 21:37
2
KUDOS
U r correct. It can be 1 or 0 in each statement and both statements together.

Since we cant COME TO A CONCLUSION IF ITS EVEN(0) OR ODD(1) its INSUFF

E)

Kudos [?]: 10 [2], given: 0

Manager
Joined: 11 Nov 2008
Posts: 108

Kudos [?]: 10 [1], given: 5

Location: Indonesia
GMAT 1: 720 Q49 V40
GPA: 3.64
WE: Asset Management (Investment Banking)

### Show Tags

09 Dec 2008, 21:40
1
KUDOS
cramya wrote:
U r correct. It can be 1 or 0 in each statement and both statements together.

Since we cant COME TO A CONCLUSION IF ITS EVEN(0) OR ODD(1) its INSUFF

E)

Well my point exactly (although we come to a different conclusion at that). Considering that we don't really need a specific value in this question so long as we can determine whether N is even or not right?

Kudos [?]: 10 [1], given: 5

SVP
Joined: 30 Apr 2008
Posts: 1863

Kudos [?]: 624 [1], given: 32

Location: Oklahoma City
Schools: Hard Knocks

### Show Tags

09 Dec 2008, 23:21
1
KUDOS
A = Statement 1 is sufficient while Statement 2 is not sufficient.
B = Statement 2 is sufficient while Statement 1 is not sufficient
C = Statements 1 and 2 together are sufficient while NEITHER statement ALONE is sufficient
D = Both Statements 1 and 2 are sufficient (independent of the other)
E = Together, Statements 1 and 2 are NOT sufficient.

The answer cannot be D because when Statement 1 is Insufficient, the only possible answer choices left is B, C or E. D is not even an option because A requires #1 to be sufficient and D requires #1 to be sufficient independently of #2.

#1 is insufficient because N^2 will only be equal to N when N = 0 or +1. Because of this, we do not know if N is even because 0 is even, but +1 is odd.

I believe the answer should be E because # is insufficient also.

N could be 1, 0 or even -1. Same thing as #1...even & odd possibilities means that we cannot give a definite answer.

Together will not help because we have 0 and 1 as options for both Statements.

ozzie123 wrote:
Hello,

Is integer integer N even?

1. N^2 = N
2. N = N^3

My answer is D but the answer from the system is E, how is this possible?

Both statement will give us 1 or 0 in which neither is even and it's sufficient to answer the problem.

_________________

------------------------------------
J Allen Morris
**I'm pretty sure I'm right, but then again, I'm just a guy with his head up his a.

GMAT Club Premium Membership - big benefits and savings

Kudos [?]: 624 [1], given: 32

Manager
Joined: 14 Oct 2008
Posts: 160

Kudos [?]: 64 [5], given: 0

### Show Tags

09 Dec 2008, 23:37
5
KUDOS
ozzie123 wrote:
Hello,

Is integer integer N even?

1. N^2 = N
2. N = N^3

My answer is D but the answer from the system is E, how is this possible?

Both statement will give us 1 or 0 in which neither is even and it's sufficient to answer the problem.

0 is Even , thats were you are getting confused.

Kudos [?]: 64 [5], given: 0

Manager
Joined: 11 Nov 2008
Posts: 108

Kudos [?]: 10 [1], given: 5

Location: Indonesia
GMAT 1: 720 Q49 V40
GPA: 3.64
WE: Asset Management (Investment Banking)

### Show Tags

10 Dec 2008, 00:05
1
KUDOS
gameCode wrote:

0 is Even , thats were you are getting confused.

Ah gameCode, thank you!

Kudos [?]: 10 [1], given: 5

Intern
Joined: 12 Feb 2010
Posts: 5

Kudos [?]: 37 [0], given: 0

Schools: ISB, HBS, LSB, Johnson

### Show Tags

18 Feb 2010, 02:26
Well, its not a great question i think. -1.

Kudos [?]: 37 [0], given: 0

Intern
Joined: 21 Dec 2010
Posts: 2

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

### Show Tags

18 Feb 2011, 06:34
1
KUDOS
St. 1:
N^2 = N
N^2 - N = 0
N ( N-1)= 0

N= 0 or 1 (not sufficient)

St. 2:
N= N^3
N - N^3 = 0
N (1 - N^2) = 0
N (1-N) (1+N) = 0

N= 0 or 1 or -1 (not sufficient)

Combining 1 and 2
N= 0 or 1

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

Math Expert
Joined: 02 Sep 2009
Posts: 42280

Kudos [?]: 132894 [1], given: 12391

### Show Tags

18 Feb 2011, 06:58
1
KUDOS
Expert's post
First note that: zero is an even integer.

An even number is an integer that is "evenly divisible" by 2, i.e., divisible by 2 without a remainder.
An even number is an integer of the form $$n=2k$$, where $$k$$ is an integer.

So for $$k=0$$ --> $$n=2*0=0$$.

As for the question:

Is integer N even?

(1) N^2 = N --> $$n(n-1)=0$$ --> either $$n=0=even$$ or $$n=1=odd$$. Not sufficient.
(2) N^3 = N --> $$n(n-1)(n+1)=0$$ --> $$n=0=even$$ or $$n=1=odd$$ or $$n=-1=odd$$. Not sufficient.

(1)+(2) $$n$$ can still be zero, so even or 1, so odd. Not sufficient.

For more on number properties check: math-number-theory-88376.html

Hope it helps.
_________________

Kudos [?]: 132894 [1], given: 12391

Senior Manager
Joined: 08 Nov 2010
Posts: 392

Kudos [?]: 129 [0], given: 161

### Show Tags

18 Feb 2011, 07:04
i understand this question perfectly and i got it right,

but how come, if i decide to divide both sides with N - it should keep the value the same.

but i would get N=1 only.

can someone make it clearer for me?

why cant i divide all in N and still get the full answer?

thanks.
_________________

Kudos [?]: 129 [0], given: 161

Math Expert
Joined: 02 Sep 2009
Posts: 42280

Kudos [?]: 132894 [0], given: 12391

### Show Tags

18 Feb 2011, 07:11
144144 wrote:
i understand this question perfectly and i got it right,

but how come, if i decide to divide both sides with N - it should keep the value the same.

but i would get N=1 only.

can someone make it clearer for me?

why cant i divide all in N and still get the full answer?

thanks.

Never reduce equation by variable (or expression with variable), if you are not certain that variable (or expression with variable) doesn't equal to zero. We can not divide by zero.

So when you divide by N you assume, with no ground for it, that N does not equal to zero thus exclude a possible solution.
_________________

Kudos [?]: 132894 [0], given: 12391

Manager
Joined: 04 Dec 2009
Posts: 69

Kudos [?]: 9 [0], given: 4

Location: INDIA

### Show Tags

18 Feb 2011, 20:52
ans E for both statment n=0 or 1
_________________

MBA (Mind , Body and Attitude )

Kudos [?]: 9 [0], given: 4

Intern
Joined: 13 Jan 2011
Posts: 3

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

### Show Tags

19 Feb 2011, 01:22
Yah, I see Sangya explained that question is exactly.
We can't choose the result if it has 2 numbers : 0 and 1.
So, E is OA

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

Manager
Joined: 10 Jan 2011
Posts: 232

Kudos [?]: 81 [0], given: 25

Location: India
GMAT Date: 07-16-2012
GPA: 3.4
WE: Consulting (Consulting)

### Show Tags

20 Feb 2011, 10:49

as N can be 0 or 1
_________________

-------Analyze why option A in SC wrong-------

Kudos [?]: 81 [0], given: 25

Manager
Joined: 02 Feb 2012
Posts: 204

Kudos [?]: 6 [0], given: 105

Location: United States
GMAT 1: 770 Q49 V47
GPA: 3.08

### Show Tags

22 Feb 2012, 14:17

Kudos [?]: 6 [0], given: 105

Manager
Joined: 27 Apr 2010
Posts: 119

Kudos [?]: 129 [0], given: 61

### Show Tags

23 Feb 2012, 21:13
we know: e*e=e, o*o=o
we also know: N^2 = N*N = e*e or o*o
N^3= N*N*N = e*e*e or o*o*o
this knocks out a,b,d automatically.

together it is: N^2 = N^3, so we know it's either 0 or 1/-1. 0 = even and 1 = d so...still doesn't solve.

E.

Kudos [?]: 129 [0], given: 61

Manager
Joined: 10 Nov 2010
Posts: 246

Kudos [?]: 412 [0], given: 22

Location: India
Concentration: Strategy, Operations
GMAT 1: 520 Q42 V19
GMAT 2: 540 Q44 V21
WE: Information Technology (Computer Software)

### Show Tags

26 Feb 2012, 06:14
a) n^2=n
=> 0^2=0 or 1^2=1 as zero is even integer and and 1 is odd ---- NS
b) n= n^3
=> 0=0^3 or 1=1^3 as zero is even integer and and 1 is odd ----NS
a+b) NS

E
_________________

The proof of understanding is the ability to explain it.

Kudos [?]: 412 [0], given: 22

Intern
Joined: 15 Apr 2011
Posts: 47

Kudos [?]: 12 [0], given: 8

### Show Tags

26 Feb 2013, 09:20
Yekrut wrote:

I have also made similar mistake in the past. Practice! Practice! Practice! is the key...

Kudos [?]: 12 [0], given: 8

Intern
Joined: 10 Aug 2012
Posts: 19

Kudos [?]: 6 [1], given: 15

Location: India
Concentration: General Management, Technology
GPA: 3.96

### Show Tags

26 Feb 2013, 22:25
1
KUDOS
As we know 0 is an even number.

Is integer N even?

(1) N^2 = N => N either 0 or 1.... Not sufficient.
(2) N^3 = N => N either 0 or 1.... Not sufficient.

(1)+(2) can still be zero, so even or 1, so odd. Not sufficient.

Kudos [?]: 6 [1], given: 15

Intern
Status: VRAM
Joined: 07 Feb 2014
Posts: 5

Kudos [?]: 6 [1], given: 1

Location: India
Concentration: Finance, Marketing
GMAT Date: 09-06-2014
WE: Consulting (Computer Software)

### Show Tags

25 Feb 2014, 04:47
1
KUDOS
I guesss E for me

N=N^2 scenarios 0,1 bOTH odd and even

N=N^3 again 0 and 1 both odd and even

so cannot find even after combining hence E

Kudos [?]: 6 [1], given: 1

Re: m04 Q2   [#permalink] 25 Feb 2014, 04:47

Go to page    1   2    Next  [ 21 posts ]

Display posts from previous: Sort by

# m04 Q2

Moderator: Bunuel

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.