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# If n is an integer, is n odd?

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Joined: 02 Sep 2009
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If n is an integer, is n odd?  [#permalink]

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01 Nov 2015, 09:12
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86% (01:05) correct 14% (01:11) wrong based on 97 sessions

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If n is an integer, is n odd?

(1) 2n -1 is an odd integer

(2) n^2 - 1 is an even integer

Kudos for a correct solution.

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Re: If n is an integer, is n odd?  [#permalink]

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01 Nov 2015, 11:24
1
Statement 1: 2n -1 is odd
Value of n can be even or odd as 2n will be even
Even -Odd=odd
INSUFFICIENT

Statement 2
N^2 - 1 = even
Square of odd will be odd
Odd- Odd = Even
Thus n is odd
SUFFICIENT

OME B
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Re: If n is an integer, is n odd?  [#permalink]

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01 Nov 2015, 14:28
Bunuel wrote:
If n is an integer, is n odd?

(1) 2n -1 is an odd integer

(2) n^2 - 1 is an even integer

Kudos for a correct solution.

The question asks whether n is an ODD integer ?

Statement 1 says (2n -1) = ODD. In fact, 2n-1 will always be ODD irrespective the value of n. NOT Sufficient.

Statement 2 says ($$n^2$$ - 1) = Even. That means the value of $$n^2$$ is ODD. So n = ODD as $$(ODD)^2$$ is ODD. Sufficient.

So Option (B) wins.
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Re: If n is an integer, is n odd?  [#permalink]

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02 Nov 2015, 08:54
orig q is (is n= odd)

1. 2n-1=odd i.e. 2n=even, but 2n is always even so, 1 is not suff.

2. n2-1 = even i.e. n2=odd but sqaure root of odd no is always odd so suff

ANS :B
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Re: If n is an integer, is n odd?  [#permalink]

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22 Aug 2016, 09:02
Here is my approach =>
here we need to find whether n is odd or not
Statement 1 => 2n-1=odd
wait a minute
2n-1 is always odd irrespective of n being even or odd
=> insuff
Statement 2 => n2-1=even => n^2=odd -> n must be odd too as POWER does not effect the even odd nature of any number
SMAShH that B
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Re: If n is an integer, is n odd?  [#permalink]

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30 Nov 2018, 13:09
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Re: If n is an integer, is n odd?   [#permalink] 30 Nov 2018, 13:09
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# If n is an integer, is n odd?

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