Last visit was: 25 Apr 2026, 18:16 It is currently 25 Apr 2026, 18:16
Home
Messages
Tests
Schools
Events
Close
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
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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
User avatar
Manat
User avatar
Joined: 11 Jun 2018
Last visit: 22 Feb 2020
Posts: 121
Own Kudos:
72
 [8]
Given Kudos: 79
Schools: DeGroote "22 (II) Molson '22 (A)
GMAT 1: 500 Q39 V21
Schools: DeGroote "22 (II) Molson '22 (A)
GMAT 1: 500 Q39 V21
Posts: 121
Kudos: 72
 [8]
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 03 Feb 2019, 10:52
2
Kudos
Add Kudos
6
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
C
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

95% (hard)

Question Stats:

27% (01:15) correct 73% (01:24) wrong based on 154 sessions

History

Date
Time
Result
Not Attempted Yet
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd?

(1) X and Y are odd.

(2) Z is even.
ShowHide Answer
Official Answer
C
User avatar
KanishkM
User avatar
Joined: 09 Mar 2018
Last visit: 18 Dec 2021
Posts: 755
Own Kudos:
512
 [2]
Given Kudos: 123
Location: India
Schools: DeGroote'21 Desautels '21 NUS '21
Schools: DeGroote'21 Desautels '21 NUS '21
Posts: 755
Kudos: 512
 [2]
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 03 Feb 2019, 11:14
1
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
Manat
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd?

(1) X and Y are odd.

(2) Z is even.
Show more

So

z can be even or fractions as well



1) X and Y are odd.

X^2−Y^3−2Z
Can be even or odd.

2) This doesn't tell anything about x and y

Lets combine both of them

X^2 - Y^3 - 2z

Will always be even - 2 * z

Even - Even

Even

Answers the question as a No

C
User avatar
chetan2u
User avatar
GMAT Expert
Joined: 02 Aug 2009
Last visit: 25 Apr 2026
Posts: 11,229
Own Kudos:
45,020
 [1]
Given Kudos: 335
Status:Math and DI Expert
Location: India
Concentration: Human Resources, General Management
GMAT Focus 1: 735 Q90 V89 DI81
Products:
My Reviews
Expert
Expert reply
GMAT Focus 1: 735 Q90 V89 DI81
Posts: 11,229
Kudos: 45,020
 [1]
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 04 Feb 2019, 00:40
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
Manat
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd?

(1) X and Y are odd.

(2) Z is even.
Show more


\(X^2−Y^3−2Z\)

X, y and Z are non-zero numbers, so they can be fractions or integers...



(1) X and Y are odd.
\(x^2-Y^3\) is surely even. Now it depends on 2Z..
say z is an integer ans is EVEN
say Z is a fraction, \(\frac{1}{2}\), then ans is ODD
Insuff

(2) Z is even
Nothing about X and Y
insuff

Combined..
all are integers, so ans is always EVEN
Sufficient

C
User avatar
Gmat2Cracker
User avatar
Joined: 30 Oct 2018
Last visit: 07 Jun 2020
Posts: 53
Own Kudos:
17
Given Kudos: 84
Location: India
Concentration: General Management, Entrepreneurship
Schools: IE '22 (A)
WE:Information Technology (Computer Software)
Schools: IE '22 (A)
Posts: 53
Kudos: 17
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 04 Feb 2019, 01:16
Kudos
Add Kudos
Bookmarks
Bookmark this Post
good question.. missed the part that z can also be a fraction and marked A
User avatar
Archit3110
User avatar
Major Poster
Joined: 18 Aug 2017
Last visit: 25 Apr 2026
Posts: 8,630
Own Kudos:
5,190
Given Kudos: 243
Status:You learn more from failure than from success.
Location: India
Concentration: Sustainability, Marketing
GMAT Focus 1: 545 Q79 V79 DI73
GMAT Focus 2: 645 Q83 V82 DI81
GPA: 4
WE:Marketing (Energy)
Products:
GMAT Club Tests Forum Quiz
GMAT Focus 2: 645 Q83 V82 DI81
Posts: 8,630
Kudos: 5,190
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? Updated on: 05 Feb 2019, 04:04
Originally posted by Archit3110 on 05 Feb 2019, 03:39.
Last edited by Archit3110 on 05 Feb 2019, 04:04, edited 1 time in total.
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Manat
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd?

(1) X and Y are odd.

(2) Z is even.
Show more


#1
x& y are odd
X^2−Y^3−2Z ; would always be even ;
X^2−Y^3−2Z; would be odd only if z is even i.e "1/2 "fraction ;
insufficieint

#2
z even ; not sufficient , values of x,y not given

from 1&2
x & y are odd and z is even

so in that case X^2−Y^3−2Z would be odd if z is even fraction 1/2 and even when z is an integer..


IMO C
User avatar
KanishkM
User avatar
Joined: 09 Mar 2018
Last visit: 18 Dec 2021
Posts: 755
Own Kudos:
512
Given Kudos: 123
Location: India
Schools: DeGroote'21 Desautels '21 NUS '21
Schools: DeGroote'21 Desautels '21 NUS '21
Posts: 755
Kudos: 512
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 05 Feb 2019, 03:51
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Archit3110
Manat
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd?

(1) X and Y are odd.

(2) Z is even.


#1
x& y are odd
X^2−Y^3−2Z ; would always be even ;
X^2−Y^3−2Z; would be odd only if z is even i.e "1/2 "fraction ;
insufficieint

#2
z even ; not sufficient , values of x,y not given

from 1&2
x & y are odd and z is even

so in that case X^2−Y^3−2Z would be odd if z is even fraction 1/2 and even when z is an integer..

in #2 its given z is even ; it can be an integer or fraction as well...
X^2−Y^3−2Z
x & y are odd and z = 2 or even integer ; we would get even value
and
x& y are odd and z = 1/2 , we would get odd value
IMO E
Show more

Archit3110 but z = 1/2 is not even, because when you solve it, 0.5, is an odd fraction(non-zero number), this when used in statement A could have answered the question as Yes

That is why when we combine, it says that z is even

We could have taken 0.4 which is 2/5

odd -odd - 4/5
3-5 - 0.8
Even - Even
Even

Let me know what you think about this
User avatar
Archit3110
User avatar
Major Poster
Joined: 18 Aug 2017
Last visit: 25 Apr 2026
Posts: 8,630
Own Kudos:
5,190
Given Kudos: 243
Status:You learn more from failure than from success.
Location: India
Concentration: Sustainability, Marketing
GMAT Focus 1: 545 Q79 V79 DI73
GMAT Focus 2: 645 Q83 V82 DI81
GPA: 4
WE:Marketing (Energy)
Products:
GMAT Club Tests Forum Quiz
GMAT Focus 2: 645 Q83 V82 DI81
Posts: 8,630
Kudos: 5,190
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 05 Feb 2019, 04:03
Kudos
Add Kudos
Bookmarks
Bookmark this Post
KanishkM
Archit3110
Manat
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd?

(1) X and Y are odd.

(2) Z is even.


#1
x& y are odd
X^2−Y^3−2Z ; would always be even ;
X^2−Y^3−2Z; would be odd only if z is even i.e "1/2 "fraction ;
insufficieint

#2
z even ; not sufficient , values of x,y not given

from 1&2
x & y are odd and z is even

so in that case X^2−Y^3−2Z would be odd if z is even fraction 1/2 and even when z is an integer..

in #2 its given z is even ; it can be an integer or fraction as well...
X^2−Y^3−2Z
x & y are odd and z = 2 or even integer ; we would get even value
and
x& y are odd and z = 1/2 , we would get odd value
IMO E

Archit3110 but z = 1/2 is not even, because when you solve it, 0.5, is an odd integer(non-zero number), this when used in statement A could have answered the question as Yes

That is why when we combine, it says that z is even

We could have taken 0.4 which is 2/5

odd -odd - 4/5
3-5 - 0.8
Even - Even
Even

Let me know what you think about this
Show more

KanishkM ; fractions cannot be even or odd ; only whole numbers can be categorised as even or odd..
I understood where i went wrong in my approach ; thanks..
User avatar
chetan2u
User avatar
GMAT Expert
Joined: 02 Aug 2009
Last visit: 25 Apr 2026
Posts: 11,229
Own Kudos:
45,020
Given Kudos: 335
Status:Math and DI Expert
Location: India
Concentration: Human Resources, General Management
GMAT Focus 1: 735 Q90 V89 DI81
Products:
My Reviews
Expert
Expert reply
GMAT Focus 1: 735 Q90 V89 DI81
Posts: 11,229
Kudos: 45,020
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 05 Feb 2019, 04:26
Kudos
Add Kudos
Bookmarks
Bookmark this Post
KanishkM
Archit3110
Manat
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd?

(1) X and Y are odd.

(2) Z is even.


#1
x& y are odd
X^2−Y^3−2Z ; would always be even ;
X^2−Y^3−2Z; would be odd only if z is even i.e "1/2 "fraction ;
insufficieint

#2
z even ; not sufficient , values of x,y not given

from 1&2
x & y are odd and z is even

so in that case X^2−Y^3−2Z would be odd if z is even fraction 1/2 and even when z is an integer..

in #2 its given z is even ; it can be an integer or fraction as well...
X^2−Y^3−2Z
x & y are odd and z = 2 or even integer ; we would get even value
and
x& y are odd and z = 1/2 , we would get odd value
IMO E

Archit3110 but z = 1/2 is not even, because when you solve it, 0.5, is an odd fraction(non-zero number), this when used in statement A could have answered the question as Yes

That is why when we combine, it says that z is even

We could have taken 0.4 which is 2/5

odd -odd - 4/5
3-5 - 0.8
Even - Even
Even

Let me know what you think about this
Show more

EVEN or ODD means they are integer also
User avatar
AliciaSierra
User avatar
Joined: 17 Mar 2014
Last visit: 14 Jun 2024
Posts: 736
Own Kudos:
648
Given Kudos: 1,350
Products:
My Reviews
Posts: 736
Kudos: 648
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 05 Feb 2019, 21:18
Kudos
Add Kudos
Bookmarks
Bookmark this Post
KanishkM
Archit3110
Manat
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd?

(1) X and Y are odd.

(2) Z is even.


#1
x& y are odd
X^2−Y^3−2Z ; would always be even ;
X^2−Y^3−2Z; would be odd only if z is even i.e "1/2 "fraction ;
insufficieint

#2
z even ; not sufficient , values of x,y not given

from 1&2
x & y are odd and z is even

so in that case X^2−Y^3−2Z would be odd if z is even fraction 1/2 and even when z is an integer..

in #2 its given z is even ; it can be an integer or fraction as well...
X^2−Y^3−2Z
x & y are odd and z = 2 or even integer ; we would get even value
and
x& y are odd and z = 1/2 , we would get odd value
IMO E

Archit3110 but z = 1/2 is not even, because when you solve it, 0.5, is an odd fraction(non-zero number), this when used in statement A could have answered the question as Yes

That is why when we combine, it says that z is even

We could have taken 0.4 which is 2/5

odd -odd - 4/5
3-5 - 0.8
Even - Even
Even

Let me know what you think about this
Show more




Is EVEN or ODD mean INTEGER Only?

So 2.2 is not even fraction ?
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 25 Apr 2026
Posts: 109,830
Own Kudos:
811,286
Given Kudos: 105,886
Products:
GMAT Club Tests Forum Quiz
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,830
Kudos: 811,286
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 05 Feb 2019, 21:40
Kudos
Add Kudos
Bookmarks
Bookmark this Post
ammuseeru
KanishkM
Archit3110


#1
x& y are odd
X^2−Y^3−2Z ; would always be even ;
X^2−Y^3−2Z; would be odd only if z is even i.e "1/2 "fraction ;
insufficieint

#2
z even ; not sufficient , values of x,y not given

from 1&2
x & y are odd and z is even

so in that case X^2−Y^3−2Z would be odd if z is even fraction 1/2 and even when z is an integer..

in #2 its given z is even ; it can be an integer or fraction as well...
X^2−Y^3−2Z
x & y are odd and z = 2 or even integer ; we would get even value
and
x& y are odd and z = 1/2 , we would get odd value
IMO E

Archit3110 but z = 1/2 is not even, because when you solve it, 0.5, is an odd fraction(non-zero number), this when used in statement A could have answered the question as Yes

That is why when we combine, it says that z is even

We could have taken 0.4 which is 2/5

odd -odd - 4/5
3-5 - 0.8
Even - Even
Even

Let me know what you think about this




Is EVEN or ODD mean INTEGER Only?

So 2.2 is not even fraction ?
Show more

2.2 is NOT even or ODD.

Only integers can be even or odd:

An even number is an integer that is "evenly divisible" by 2, i.e., divisible by 2 without a remainder.

An odd number is an integer that is not evenly divisible by 2.
avatar
Debashis Roy
avatar
Joined: 23 Aug 2017
Last visit: 15 Dec 2019
Posts: 90
Own Kudos:
21
Given Kudos: 9
Schools: ISB '21 (A)
Schools: ISB '21 (A)
Posts: 90
Kudos: 21
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 01 Mar 2019, 07:31
Kudos
Add Kudos
Bookmarks
Bookmark this Post
chetan2u VeritasKarishma
from 1&2
x & y are odd and z is even

Even x and y can also be fractions along with z...
Are we accounting for them as well....For some values the result can turn out to be a negative fraction as well...

if z= 1/4...then 2z=1/2...an even fraction....but for z=1/6..2z=1/3....So 2 different nature of the fraction may be obtained which could give us different(even/odd) value..

Thanks in advance
User avatar
chetan2u
User avatar
GMAT Expert
Joined: 02 Aug 2009
Last visit: 25 Apr 2026
Posts: 11,229
Own Kudos:
45,020
Given Kudos: 335
Status:Math and DI Expert
Location: India
Concentration: Human Resources, General Management
GMAT Focus 1: 735 Q90 V89 DI81
Products:
My Reviews
Expert
Expert reply
GMAT Focus 1: 735 Q90 V89 DI81
Posts: 11,229
Kudos: 45,020
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 01 Mar 2019, 19:30
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Debashis Roy
chetan2u VeritasKarishma
from 1&2
x & y are odd and z is even

Even x and y can also be fractions along with z...
Are we accounting for them as well....For some values the result can turn out to be a negative fraction as well...

if z= 1/4...then 2z=1/2...an even fraction....but for z=1/6..2z=1/3....So 2 different nature of the fraction may be obtained which could give us different(even/odd) value..

Thanks in advance
Show more


When we say a number or a variable is odd or even, it means they are integers.
Only integers can be even and odd, so you cannot take fractions here for x, y and z.
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,986
Own Kudos:
1,118
Posts: 38,986
Kudos: 1,118
If X, Y and Z are non-zero numbers, is X^2−Y^3−2Z odd? 14 Dec 2023, 10:52
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.
Moderators:
Bunuel
Math Expert
109830 posts
kingbucky
498 posts
Gmat860sanskar
212 posts