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

Redeem

Inequalities with two inequality signs

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Senior | Next Rank: 100 Posts
Posts: 95
Joined: Tue Sep 13, 2011 3:19 pm
Thanked: 3 times
GMAT Score:710

Inequalities with two inequality signs

by massi2884 » Tue May 15, 2012 10:48 am
Hi, I have a doubt. How can we manipulate inequalities with two inequality signs?

For example this one: x + 2 < y < x + 6
If I move the numbers to the other side changing the signs, I obtain the following:
x < y -2 - 6 < x

But it looks weird because it's like x < y - 8 < x

Thanks.
Top
Source: — Problem Solving |
Master | Next Rank: 500 Posts
Posts: 142
Joined: Thu Apr 26, 2012 3:24 am
Location: India
Thanked: 28 times

by mathbyvemuri » Tue May 15, 2012 7:21 pm
we can't subtract 2 at one inequality and 6 at another inequality at a time.
x + 2 < y < x + 6
First subtract 2 all over:
x < y-2 < x+4
Then subtract 6 all over:
x-6 < y-8 < x-2

or you can subtract 8 at both inequalities at a time
Top
Master | Next Rank: 500 Posts
Posts: 109
Joined: Wed Feb 15, 2012 7:09 am
Thanked: 8 times
Followed by:2 members

by ankita1709 » Tue May 15, 2012 10:01 pm
Another way can be deal with the each of the inequalities separately
y<x+6 and y>x+2

This method is really helpful when there are quadratics or higher power involved
Top
Post new topic Post Reply
• Page 1 of 1