Q from GMAT Prep

This topic has expert replies
Source: — Data Sufficiency |

Legendary Member
Posts: 1448
Joined: Tue May 17, 2011 9:55 am
Location: India
Thanked: 375 times
Followed by:53 members

by Frankenstein » Fri Jul 01, 2011 2:42 am
Hi,
From(1): x-y>-2
if x = 2, y=1 then xy=2 >0
if x = 2, y=0 then xy=0
Not sufficient
From(2): x-2y < -6
if x=2, y=5, xy =10>0
if x=-2, y=5, xy=-10<0
Not sufficient
Both(1)&(2):
x-y > -2 and 2y-x > 6
So, adding we get y>4
x>y-2
As y>4, y-2>2
So, x>y-2>2
i.e.x>2 and y>4
Product of xy is always positive
Sufficient

Hence, C
Cheers!

Things are not what they appear to be... nor are they otherwise

Junior | Next Rank: 30 Posts
Posts: 13
Joined: Fri May 27, 2011 4:32 am

by Mumbai » Fri Jul 08, 2011 3:58 am
thanks Frank... this helps a lot :)

Master | Next Rank: 500 Posts
Posts: 135
Joined: Thu May 05, 2011 9:00 am
Thanked: 4 times
Followed by:1 members
GMAT Score:700

by mirantdon » Fri Jul 08, 2011 12:11 pm
+1 for C.
x>2 and y>4 .
the above poster seals it .!

User avatar
Master | Next Rank: 500 Posts
Posts: 461
Joined: Tue May 10, 2011 9:09 am
Location: pune
Thanked: 36 times
Followed by:3 members

by amit2k9 » Sat Jul 09, 2011 4:27 am
a x> y+2 where x =3,1 for y=1,-10. not sufficient.

b y> (x+6)/2 hence x and y can have positive and negative values. not sufficient.


a+b y>4 hence in x-y>-2 means for y=5, x= 3. thus x,y both >0/

sufficient. C it is.
For Understanding Sustainability,Green Businesses and Social Entrepreneurship visit -https://aamthoughts.blocked/
(Featured Best Green Site Worldwide-https://bloggers.com/green/popular/page2)