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

It is currently 18 Oct 2019, 20:14

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.

Close

Request Expert Reply

Confirm Cancel

Is xy > 24?

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Find Similar Topics 
Retired Moderator
User avatar
S
Joined: 18 Sep 2014
Posts: 1093
Location: India
GMAT ToolKit User Reviews Badge
Is xy > 24?  [#permalink]

Show Tags

New post 06 Apr 2016, 05:20
5
00:00
A
B
C
D
E

Difficulty:

  75% (hard)

Question Stats:

58% (02:32) correct 42% (02:25) wrong based on 124 sessions

HideShow timer Statistics

Is \(xy > 24\)?

1. \(y - 2 < x\)
2. \(2y > x + 8\)
Math Expert
avatar
V
Joined: 02 Aug 2009
Posts: 7979
Re: Is xy > 24?  [#permalink]

Show Tags

New post 06 Apr 2016, 05:34
3
Nevernevergiveup wrote:
Is \(xy > 24\)?

1. \(y - 2 < x\)
2. \(2y > x + 8\)


Hi,

Is \(xy > 24\)..

At the very first glance, we can rule out that any statement can be sufficient alone..
each statement has an equality sign and we do not know if the two are fraction, integer, positive or negative..

If time is running out, therefore C is the BEST bet..

lets see the statements--
1. \(y - 2 < x\)
if x=5, y=2.. ans NO
x= 8, y =5.. ans YES
Insuff

2. \(2y > x + 8\)
x= -6, y=2 .... NO
x=6, y=8.. YES
Insuff

Combined..
since x>y-2 and 2y > x+8
I can substitute x as y-2, since that is more than the least value of x..
2y>y-2+8
2y-y>6..
y>6..
if y>6 and x>y-2 x>6-2 or x>4..
therefore xy> 6*4...OR xy>24
Suff


C
_________________
Manager
Manager
avatar
B
Joined: 01 Jul 2010
Posts: 58
Location: India
GMAT 1: 660 Q43 V38
GPA: 3.4
GMAT ToolKit User
Re: Is xy > 24?  [#permalink]

Show Tags

New post 06 Apr 2016, 05:50
Hi Chetan,
I cant understand this ' since that is more than the least value of x'.
Cant y-2 be big that it cant be substituted here ?

Thanks for your help.
-Arun
Math Expert
avatar
V
Joined: 02 Aug 2009
Posts: 7979
Re: Is xy > 24?  [#permalink]

Show Tags

New post 06 Apr 2016, 06:08
raarun wrote:
Hi Chetan,
I cant understand this ' since that is more than the least value of x'.
Cant y-2 be big that it cant be substituted here ?

Thanks for your help.
-Arun


Hi arun,

since x>y-2and 2y > x+8
I can substitute x as y-2, since that is more than the least value of x..
Other way of SAMETHING can be
Now 2y>x+8...(i)
But x>y-2...(ii)

add the bigger parts that is 2y and x ...
And the smaller parts x+8 and y-2..

2y+x>x+8+y-2..
2y+x-x-y>8-2..
y>6
Hope it helps
_________________
Manager
Manager
avatar
B
Joined: 01 Jul 2010
Posts: 58
Location: India
GMAT 1: 660 Q43 V38
GPA: 3.4
GMAT ToolKit User
Is xy > 24?  [#permalink]

Show Tags

New post 06 Apr 2016, 08:12
1
Thanks a lot chetan.I understood.

This can also be solved by the following methods
Combining statement 1 and 2 by adding them together.
\(y−2<x\)
\(x+8<2y\)
solved the inequality wrongly
\(6 < x+y\) and ended with ans E
The addition should also result in 6 < y

This can also be solved by subtracting 1 from 2.
\(y−2<x\)---1
\(2y>x+8\) ----2

i got \(y >6\)

Both the cases will lead to answer C



-Arun
Manager
Manager
avatar
Joined: 24 May 2013
Posts: 76
GMAT ToolKit User
Re: Is xy > 24?  [#permalink]

Show Tags

New post 06 Apr 2016, 12:50
1
Is xy>24?

1. y−2<x
2. 2y>x+8


Individually both the inequalities are in sufficient.

Combining the two and plotting we can see that the shaded region of interest has xy>24.

hance C
Attachments

Inequality.png
Inequality.png [ 10.44 KiB | Viewed 1720 times ]

Manager
Manager
User avatar
S
Joined: 28 Nov 2017
Posts: 141
Location: Uzbekistan
Re: Is xy > 24?  [#permalink]

Show Tags

New post 10 Apr 2018, 00:52
Nevernevergiveup wrote:
Is \(xy > 24\)?

1. \(y - 2 < x\)
2. \(2y > x + 8\)


It is clear that first and second statements are not sufficient separately.
However, if we take them together, we have
y-2<x<2y-8.
Thus,
2y-8>y-2 resulting in y>6 and x>4.
This is sufficient to answer the question.
_________________
Kindest Regards!
Tulkin.
GMAT Club Bot
Re: Is xy > 24?   [#permalink] 10 Apr 2018, 00:52
Display posts from previous: Sort by

Is xy > 24?

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  





Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne