Last visit was: 26 Apr 2026, 10:49 It is currently 26 Apr 2026, 10:49
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
555-605 (Medium)|   Algebra|      
User avatar
Niveditha28
User avatar
Joined: 08 Sep 2019
Last visit: 04 Sep 2022
Posts: 56
Own Kudos:
26
Given Kudos: 101
GMAT 1: 600 Q43 V30
GMAT 1: 600 Q43 V30
Posts: 56
Kudos: 26
Is x/y = 1 ? (1) x^3/y^3 = 1 (2) x^2/y^2 = 1 Updated on: 19 Oct 2020, 05:47
Originally posted by Niveditha28 on 19 Oct 2020, 04:56.
Last edited by Bunuel on 19 Oct 2020, 05:47, edited 1 time in total.
Renamed the topic, edited the question and added the OA.
Kudos
Add Kudos
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

25% (medium)

Question Stats:

65% (00:38) correct 35% (00:37) wrong based on 48 sessions

History

Date
Time
Result
Not Attempted Yet
Is x/y = 1 ?

(1) x^3/y^3 = 1
(2) x^2/y^2 = 1
ShowHide Answer
Official Answer
A
User avatar
VoltAmpere
User avatar
Joined: 10 Mar 2020
Last visit: 23 Dec 2021
Posts: 56
Own Kudos:
46
Given Kudos: 63
Posts: 56
Kudos: 46
Is x/y = 1 ? (1) x^3/y^3 = 1 (2) x^2/y^2 = 1 19 Oct 2020, 05:09
Kudos
Add Kudos
Bookmarks
Bookmark this Post
is x/y=1?

For statement 1: SUFFICIENT
x^3/y^3=1
x^3=y^3
x^3-y^3=0
(x-y)(x^2+xy+y^2)=0
x-y=0; x=y
(x^2+xy+y^2) x would lead to imaginary y
so x/y=1
or
x^3/y^3=1
(x/y)^3=1
x/y=1^(1/3)
x/y=1

For statement 2: INSUFFICIENT
x^2/y^2=1
(x/y)^2=1
x/y=sqrt(1)
x/y=-1; x/y=1
TWO VALUES ARE POSSIBLE, INSUFFICIENT

IMO CORRECT ANSWER IS A
User avatar
chetan2u
User avatar
GMAT Expert
Joined: 02 Aug 2009
Last visit: 26 Apr 2026
Posts: 11,229
Own Kudos:
45,022
 [2]
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: 45,022
 [2]
Is x/y = 1 ? (1) x^3/y^3 = 1 (2) x^2/y^2 = 1 19 Oct 2020, 05:43
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Niveditha28
Bunuel chetan2u

Can you please help me solve this question?

IS x/y = 1

St1 : X^3/y^3 = 1
St2 : X^2/Y^2 = 1
Show more


\(\frac{x^3}{y^3}=(\frac{x}{y})^3==1^3=1\)....x/y=1
Now anything to power 0 is 1, a^0=1, or 1 to the power of anything, 1^6=1, or -1 to power of even integer.

\(\frac{x^2}{y^2}=(\frac{x}{y})^2=1=(-1)^2=1^2\)
So x/y can be 1 or -1

A
User avatar
gmatcafe
User avatar
Joined: 27 Sep 2020
Last visit: 25 Nov 2022
Posts: 182
Own Kudos:
288
 [1]
Given Kudos: 97
Location: Uzbekistan
Concentration: Finance, Strategy
Schools: Marshall '25 Smeal Carey Ross '25
GPA: 3.73
WE:Consulting (Consulting)
Schools: Marshall '25 Smeal Carey Ross '25
Posts: 182
Kudos: 288
 [1]
Is x/y = 1 ? (1) x^3/y^3 = 1 (2) x^2/y^2 = 1 19 Oct 2020, 20:06
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Is x/y = 1 ?

(1) x^3/y^3 = 1
x^3/y^3=(x/y)^3=1 x/y=1 Sufficient.

(2) x^2/y^2 = 1
x^2/y^2=(x/y)^2=1 x/y can be 1 or -1. Insufficient. A)
User avatar
MathRevolution
User avatar
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Last visit: 27 Sep 2022
Posts: 10,063
Own Kudos:
20,007
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Expert
Expert reply
GMAT 1: 760 Q51 V42
Posts: 10,063
Kudos: 20,007
Is x/y = 1 ? (1) x^3/y^3 = 1 (2) x^2/y^2 = 1 20 Oct 2020, 11:01
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Forget the conventional way to solve DS questions.

We will solve this DS question using the variable approach.

The first step of the Variable Approach: The first step and the priority is to modify and recheck the original condition and the question to suit the type of information given in the condition.

To master the Variable Approach, visit https://www.mathrevolution.com and check our lessons and proven techniques to score high in DS questions.

Learn the 3 steps. [Watch lessons on our website to master these 3 steps]

Step 1 of the Variable Approach: Modifying and rechecking the original condition and the question.

We have to find Is \(\frac{x}{y} = 1\).

=> \(\frac{x}{y} = 1\)

=> x = y

So, we have to find whether x = y?

Condition(1) tells us that \(\frac{x^3}{y^3} = 1\).

=> \(x^3 = y^3\)

=> The third power of 'x' and 'y' will only be equal when x = y - Is x = y - YES

Since the answer is a unique YES , condition(1) alone is sufficient by CMT 1.


Condition(2) tells us that \(\frac{x^2}{y^2} = 1\).

=> \(x^2 = y^2\)

=> Since, 'x' and 'y' are raised to an even power, even the negative number raised to even power will give positive values and x could be equal to y or -y.

Since the answer is not a unique YES or NO , condition(2) alone is not sufficient by CMT 1.

Condition(1) alone is sufficient.

So, A is the correct answer.

Answer: A


SAVE TIME: By Variable Approach[MODIFICATION], check the condition quickly and separately and mark answer as A or B.
Moderators:
Bunuel
Math Expert
109837 posts
kingbucky
498 posts
Gmat860sanskar
212 posts