GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 23 Jun 2018, 07:06

### 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

# If x # y = –1, which of the following could be true?

Author Message
TAGS:

### Hide Tags

Senior Manager
Joined: 03 Mar 2010
Posts: 401
Schools: Simon '16 (M)
If x # y = –1, which of the following could be true? [#permalink]

### Show Tags

14 Sep 2011, 06:48
1
00:00

Difficulty:

45% (medium)

Question Stats:

58% (01:25) correct 42% (01:32) wrong based on 74 sessions

### HideShow timer Statistics

x#y= (x−y)^2, if x>y
x#y= x+$$y/4$$, if x≤y

If x # y = –1, which of the following could be true?

I. x=y
II. x>y
III. x<y

(A) I only
(B) II only
(C) III only
(D) I and III only
(E) I, II, and III

_________________

My dad once said to me: Son, nothing succeeds like success.

Math Forum Moderator
Joined: 20 Dec 2010
Posts: 1900
Re: If x # y = –1, which of the following could be true? [#permalink]

### Show Tags

14 Sep 2011, 08:09
As always, post your timing for below question, if possible.

x#y= (x−y)^2, if x>y
x#y= x+$$y/4$$, if x≤y

If x # y = –1, which of the following could be true?
I. x=y
II. x>y
III. x<y
(A) I only
(B) II only
(C) III only
(D) I and III only
(E) I, II, and III

(2:05)

A square can never be -ve, ruled out II.

For x=y;

x+x/4=-1; 5x=-4; x=-4/5. Possible

For x>y
x+y/4=-1

x=-1-y/4=-(y+4)/4; y=-4, x=0. Possible.

Ans: "D"
_________________
Senior Manager
Joined: 03 Mar 2010
Posts: 401
Schools: Simon '16 (M)
Re: If x # y = –1, which of the following could be true? [#permalink]

### Show Tags

14 Sep 2011, 08:25
1
fluke wrote:
For x>y
x+y/4=-1

x=-1-y/4=-(y+4)/4; y=-4, x=0. Possible.

This should be x<y.
Other than that flawless.

This custom character sometimes puzzles me.
_________________

My dad once said to me: Son, nothing succeeds like success.

Math Forum Moderator
Joined: 20 Dec 2010
Posts: 1900
Re: If x # y = –1, which of the following could be true? [#permalink]

### Show Tags

14 Sep 2011, 08:39
fluke wrote:
For x>y
x+y/4=-1

x=-1-y/4=-(y+4)/4; y=-4, x=0. Possible.

This should be x<y.
Other than that flawless.

This custom character sometimes puzzles me.

That's right. thanks
_________________
Senior Manager
Joined: 11 May 2011
Posts: 355
Re: If x # y = –1, which of the following could be true? [#permalink]

### Show Tags

14 Sep 2011, 14:16
Time: 1:00 min.

Approach -
Since, x # y = –1
=> x#y= (x−y)^2, if x>y - This equation is not possible becasue any square will yield positive value.
=> x#y= x+y/4, if x≤y - This equation is only possible and as it says - x≤y, Hence - D.

Cheers!
_________________

-----------------------------------------------------------------------------------------
What you do TODAY is important because you're exchanging a day of your life for it!
-----------------------------------------------------------------------------------------

Senior Manager
Joined: 15 Jan 2017
Posts: 361
Re: If x # y = –1, which of the following could be true? [#permalink]

### Show Tags

17 Aug 2017, 22:58
x#y = (x-y)^2 --> this rules out a -ve value (and option which says x > y; becz square can't be -ve)
so x#y = -1; we have to consider next equation --which says x < equal to y

if x+y/4= -1 --> x+y = -4 => either x = y (-2 and -2) or x less than y (y is 0; x is -4)
Thus I and III
Re: If x # y = –1, which of the following could be true?   [#permalink] 17 Aug 2017, 22:58
Display posts from previous: Sort by