IMO C
question : IS -1<x<1
s1) solving for x can be 3 or 1/3
s2) x is not 3
combining x is 1/3 suff
OA
BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course
Redeem
Featured Course
Target Test Prep GMAT OnDemand
Scott Woodbury-Stewart’s private virtual classroom — 400 hours of master-class video lessons for the GMAT Focus Edition.
- 715+ score guarantee — highest in the industry (99th percentile)
- 52 chapters · 1,500+ lessons · 4,000+ practice questions
- 400 hours of video · 1,500+ instructor-led HD smartboard lessons
- 300,000+ students accepted to Harvard, Stanford, Wharton, Booth & Sloan & more
- 24/7 live support + weekly Zoom office hours with GMAT instructors
- TTP AI Assist — 24/7 AI-powered virtual tutor for instant help
- 1,200+ flashcards + AI-powered study assistant & daily calendar
- OnDemand, LiveTeach & GMAT Bootcamp formats available
- Also: GRE, SAT Math & Executive Assessment courses
- MBA Admissions Consulting now available
- 🏆 2025 EdTech Breakthrough Award: Test Prep Solution Provider of the Year
- 200,000+ students served
- 5-day free trial — $0 to start, no auto-billing, cancel anytime
★★★★★
5.0
(559 reviews)
130-pt guarantee
$0 to start
then $127/mo
Absolutely unequal - 2
Source: Beat The GMAT — Data Sufficiency |
-
thephoenix
- Legendary Member
- Posts: 1560
- Thanked: 137 times
Stem
Is -1<x<1
Statement one
Each |x| can either have value x or -x
So |x+1| can be +ve or -ve
Same way |x-1| can be +ve or -ve
That leaves us with 2 cases
x+1 = 2(x-1)
which gives x=3
x+1 = -2(x-1)
which gives us x =-1/3
Hence Insuff
Statement two
Implies x is not 3
Combined
Since x is not 3 it has to be -3 which is within -1<x<1
Hence Suff
Is -1<x<1
Statement one
Each |x| can either have value x or -x
So |x+1| can be +ve or -ve
Same way |x-1| can be +ve or -ve
That leaves us with 2 cases
x+1 = 2(x-1)
which gives x=3
x+1 = -2(x-1)
which gives us x =-1/3
Hence Insuff
Statement two
Implies x is not 3
Combined
Since x is not 3 it has to be -3 which is within -1<x<1
Hence Suff
Whether you think you can or can't, you're right.
- Henry Ford
- Henry Ford
