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 →

Combinations Question

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Problem Solving |
Senior | Next Rank: 100 Posts
Posts: 44
Joined: Sun Feb 15, 2009 7:37 pmFollowed by: 1 member
Thanked: 3 times

by Bidisha_800 » Sun Feb 22, 2009 1:38 pm
=9*8*7*6*5!/5!*4!

=9*8*7*6/4*3*2

=18*7

=126
GMATPowerPrep Test1= 740
GMATPowerPrep Test2= 760
Kaplan Diagnostic Test= 700
Kaplan Test1=600
Kalplan Test2=670
Kalplan Test3=570
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Junior | Next Rank: 30 Posts
Posts: 26
Joined: Thu Jan 15, 2009 10:25 am

by Nole23 » Sun Feb 22, 2009 3:50 pm
Could you elaborate on your math a little bit?
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16207
Joined: Mon Dec 08, 2008 6:26 pmFollowed by: 1268 members
Location: Vancouver, BC
Thanked: 5254 times
GMAT Score:770

by Brent@GMATPrepNow » Sun Feb 22, 2009 4:16 pm
To evaluate mCr, write the first r values of m! in the numerator and r! in the deniminator.

Eg: 6C2 = (6x5)/2!
Eg: 8C3=(8x7x6)/3!
Eg: 10C4 = (10x9x8x7)/4!

To evaluate these, do not calculate the products in the numerator and denominator and then simply. Rather, simplify before multiplying.

Eg: 9C3 = (9x8x7)/3! = (9x8x7)/(3x2x1)
We have 9 in the numerator and 3 in the denominator. Simply to get: (3x8x7)/(1x2x1)
Similarly, we have 8 in the numerator and 2 in the denominator. Simply to get: (3x4x7)/(1x1x1) = 84

Hope that helps.
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1