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 →

color codes

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Legendary Member
Posts: 621
Joined: Wed Apr 09, 2008 7:13 pmFollowed by: 4 members
Thanked: 33 times
by vittalgmat » Thu Jan 01, 2009 3:38 am
John has 12 clients and he wants to use color coding to identify each client. If either a single color or a pair of two different colors can represent a client code, what is the minimum number of colors needed for the coding? Assume that changing the color order within a pair does not produce different codes.

A. 24
B. 12
C. 7
D. 6
E. 5

[spoiler]OA: E[/spoiler]
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |
Master | Next Rank: 500 Posts
Posts: 424
Joined: Sun Dec 07, 2008 5:15 pm
Location: Sydney
Thanked: 12 times

by piyush_nitt » Thu Jan 01, 2009 4:00 am
minimum number of ways in which clients can be coded =

single colours + combination of 2 colours

You can eliminate the choices A and B.

Say If John takes 4 single colours than various combinations of colours would be

4C2 = 6

i.e total (single + combination , 4+6)= 10 , that doesnot statisfy the condition.

if single colours = 5

5C2 = 10

i.e total = 15 that statisy the condition.

therefore minimum number of colours required = 5
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1