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

Redeem

Inequality

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Legendary Member
Posts: 869
Joined: Wed Aug 26, 2009 3:49 pm
Location: California
Thanked: 13 times
Followed by:3 members

Inequality

by heshamelaziry » Mon Oct 19, 2009 10:15 pm
If 0 < x < 7 and y < 9, then the lowest possible value for xy is

(1) between 60 and 70

(2) between 0 and 60

(3) 0

(4) between 0 and -70

(5) less than -70

OA 5
Last edited by heshamelaziry on Mon Oct 19, 2009 11:03 pm, edited 1 time in total.
Top
Source: — Problem Solving |
User avatar
Community Manager
Posts: 1537
Joined: Mon Aug 10, 2009 6:10 pm
Thanked: 653 times
Followed by:252 members

by papgust » Mon Oct 19, 2009 11:02 pm
IMO C
Top
Master | Next Rank: 500 Posts
Posts: 182
Joined: Sun Aug 02, 2009 7:19 pm
Thanked: 18 times
GMAT Score:680

by sanjana » Tue Oct 20, 2009 12:35 am
E is correct

From the given inequalities :

0<x<7
Max x : 6
min x : 1

y<9
Max y : 8
Min y : not defined.

To find min(xy) we need to multiply the min of x and the min of y

i.e 1 * could be any value,

the answer has to be -ve hence we can straight away eliminate a,b,c

From d and e it has to be e because -71 is less than -70 and we need the min value.
Top
Master | Next Rank: 500 Posts
Posts: 138
Joined: Mon Mar 02, 2009 12:02 pm
Thanked: 15 times

by life is a test » Tue Oct 20, 2009 6:59 am
sanjana wrote:E is correct

From the given inequalities :

0<x<7
Max x : 6
min x : 1

y<9
Max y : 8
Min y : not defined.

To find min(xy) we need to multiply the min of x and the min of y

i.e 1 * could be any value,

the answer has to be -ve hence we can straight away eliminate a,b,c

From d and e it has to be e because -71 is less than -70 and we need the min value.
Sanjana I don't understand why it has to be <-70. From what I can see there needn't be a lower bound since y can be negative infinity (hence smallest num = 6* [-infinity] = -infinity...

am i missing something? thks.
Top
Master | Next Rank: 500 Posts
Posts: 182
Joined: Sun Aug 02, 2009 7:19 pm
Thanked: 18 times
GMAT Score:680

by sanjana » Tue Oct 20, 2009 7:03 am
yes but we dont have -infinity in the answer choices and also <-70 could be -infinity. When we say <-70 we are not specifying a [articular value.
Top
Post new topic Post Reply
• Page 1 of 1