BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

is X odd if X^3 is odd??

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Data Sufficiency |
Newbie | Next Rank: 10 Posts
Posts: 8
Joined: Tue Oct 10, 2006 12:48 pm

Re: is X odd if X^3 is odd??

by zipper123 » Fri Nov 10, 2006 12:24 pm
zealzoom wrote:Hi ,

Do let me know if this is sufficient to answer the question,,,

Is X odd ??

X^3 is Odd,,,,

Cheers
zeal
Yes it is sufficient.

Assuming X is an integer (positive or negative)

X^3 can only be odd if X itself is odd

because Odd times Odd is Odd

Even times Anything is Even.
==Still Working==
Top
Junior | Next Rank: 30 Posts
Posts: 19
Joined: Fri Jul 28, 2006 12:38 pm

by zealzoom » Fri Nov 10, 2006 12:38 pm
naah thats the catch here!!!

I also think in the same way and this question seems very easy to me..

Here is the situation..

What if X = cube root 7 or cube root 3 ?? then X^3 will be odd but X itself is not an integer rather, it is an irrational number so no chance we cam certainly say that X is ODD,,,

Oh boy !! this line of reasoning really freaked me out.. let me know how do you feel ??

:(
Top
User avatar
Legendary Member
Posts: 2469
Joined: Thu Apr 20, 2006 12:09 pm
Location: BtG Underground
Thanked: 85 times
Followed by:14 members

by aim-wsc » Fri Nov 10, 2006 2:28 pm
theses nothing wrong in zipper s reply.

he's right. because he assumed that X is an integer.
so technically given condition is not sufficient. we need to know whether X is am integer or not.

pls present the full problem. :)
Top
Junior | Next Rank: 30 Posts
Posts: 19
Joined: Fri Jul 28, 2006 12:38 pm

by zealzoom » Fri Nov 10, 2006 9:33 pm
that was the problem

is X odd

a) 2x-1 is odd

b) X^3 is odd ..

My answer was B and i was pretty sure about that, but correct answer was E and reason I have already given.

DS,, its real tough to get into it ,,, :(

Any help??

Zeal
Top
Master | Next Rank: 500 Posts
Posts: 354
Joined: Tue Jun 27, 2006 9:20 pm
Thanked: 11 times
Followed by:5 members

by 800guy » Fri Nov 10, 2006 9:38 pm
where did this question come from?
Top
Senior | Next Rank: 100 Posts
Posts: 58
Joined: Tue May 23, 2006 3:35 pm
Location: Seoul, Korea
Thanked: 2 times

I agree .. it is B

by kulksnikhil » Sat Nov 11, 2006 2:37 am
zealzoom wrote:that was the problem

is X odd

a) 2x-1 is odd

b) X^3 is odd ..

My answer was B and i was pretty sure about that, but correct answer was E and reason I have already given.

DS,, its real tough to get into it ,,, :(

Any help??

Zeal


Even I feel B is right answer... for a product to be even, atleast one of the integers must be even. So if both integers are odd then the product remains odd. For x^3 to be odd, all 3 should be odd... so x has to be odd.
Top
Junior | Next Rank: 30 Posts
Posts: 19
Joined: Fri Jul 28, 2006 12:38 pm

by zealzoom » Sat Nov 11, 2006 8:09 am
800guy wrote:where did this question come from?
this was question in Kaplan GMAT test ....
Top
Post new topic Post Reply
• Page 1 of 1