BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

following is true

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
User avatar
GMAT Instructor
Posts: 3650
Joined: Wed Jan 21, 2009 4:27 am
Location: India
Thanked: 267 times
Followed by:80 members
GMAT Score:760

following is true

by sanju09 » Tue Mar 03, 2009 4:44 am
If x^2 < 9 and &#8722;2 < y < 1, then which of the following is true?

A. x < 3y
B. 3x < 2y
C. 2x > &#8722;3y
D. xy < 6
E. &#8722;xy > 6
The mind is everything. What you think you become. -Lord Buddha



Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001

www.manyagroup.com
Top
Source: — Problem Solving |
Master | Next Rank: 500 Posts
Posts: 424
Joined: Sun Dec 07, 2008 5:15 pm
Location: Sydney
Thanked: 12 times

Re: following is true

by piyush_nitt » Tue Mar 03, 2009 4:55 am
sanju09 wrote:If x^2 < 9 and &#8722;2 < y < 1, then which of the following is true?

A. x < 3y
B. 3x < 2y
C. 2x > &#8722;3y
D. xy < 6
E. &#8722;xy > 6
IMO D
Top
User avatar
Site Admin
Posts: 2567
Joined: Thu Jan 01, 2009 10:05 am
Thanked: 712 times
Followed by:550 members
GMAT Score:770

by DanaJ » Tue Mar 03, 2009 4:59 am
One neeeds to analyze what x^2 < 9 actually means: it's that x is between -3 and 3. Now, you can easily eliminate options:
A. counterexample: x = 2 and y = -1
B. counterexample: x = 2 and y = -1
C. counterexample: x = -1 and y = -1
D. in order to eliminate this one, we consider the ends of the possible values for both x and y.
a. we pick the greatest positive values for x and y:
x < 3
y < 1
xy will be smaller than 3 in this case.
b. we pick the smallest possible values for x and y on the negative side:
x < -3
y < -2
xy will indeed be smaller than 6

E. xy < -6 is not valid: consider x = 1 and y = 0.5.

Answer D
Top
Post new topic Post Reply
• Page 1 of 1