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

Redeem
TTP OnDemand GMAT Video Course
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
Start Free 5-Day Trial Read 559 Reviews →

perplexed

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 129
Joined: Mon Dec 15, 2008 11:43 pm
Location: Hyderabad
Thanked: 2 times
by naaga » Tue Mar 03, 2009 7:55 am
. If•represents one of the operations +, –, and ×,k . (r + m ) = ( k . r ) + ( k . m ) is for all numbers k, r and m?
(1) k•l is not equal to l•k for some numbers k.
(2) •represents subtraction.


I didn't understand the problem, anyone please explain this in detail
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Data Sufficiency |
Senior | Next Rank: 100 Posts
Posts: 88
Joined: Tue Mar 03, 2009 8:10 am
Thanked: 3 times

by quocbao » Tue Mar 03, 2009 8:33 am
Both choices lead to "." is subtraction, if you use substitution to check the answer.

So we have

k - ( r + m ) = k - r + k - m

or

k - r - m = 2k - r - m

It won't happen for all numbers => we can reply the question.

The answer will be D, I or II
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Legendary Member
Posts: 1035
Joined: Wed Aug 27, 2008 10:56 pmFollowed by: 1 member
Thanked: 104 times

by scoobydooby » Tue Mar 03, 2009 1:14 pm
k . (r + m ) = ( k . r ) + ( k . m )?

stmnt 1: k•l is not equal to l•k for some numbers k
=> "•" is neither addition or multiplication. "•" has be subtraction.
k-(r+m)=k-r-m (LHS)
k-r+k-m=(RHS)
or k . (r + m ) not equal to ( k . r ) + ( k . m )
sufficient


stmnt 2: "•" represents subtraction
same info as in 1 above
sufficient
hence D
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Junior | Next Rank: 30 Posts
Posts: 21
Joined: Mon Nov 24, 2008 1:56 am

by Ramp » Wed Mar 11, 2009 3:05 am
k-(r+m)=k-r-m (LHS)
k-r+k-m=(RHS)
or k . (r + m ) not equal to ( k . r ) + ( k . m )
sufficient

what if k is 0 .
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1