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 →

Permutation and combination -Finding n

Expert replies
Post new topic Post Reply
Previous Topic Next Topic
Junior | Next Rank: 30 Posts
Posts: 22
Joined: Sat Apr 19, 2014 5:24 am
by s91arvindh » Sun May 04, 2014 4:00 am
A person can invite one or more of his friends for lunch in a maximum of 500 ways. The number of friends he has may be
a) 4 b) 6 c) 8 d) 10
[spoiler]
Answers are a,b,c[/spoiler]

Note: The questions are from handouts provided
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Source: — Problem Solving |

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 May 04, 2014 5:11 am
s91arvindh wrote:A person can invite one or more of his friends for lunch in a maximum of 500 ways. The number of friends he has may be
a) 4 b) 6 c) 8 d) 10
[spoiler]
Answers are a,b,c[/spoiler]

Note: The questions are from handouts provided
This question is poorly worded. Also, Problem Solving questions on the GMAT do not have 3 correct answers. Also, Problem Solving questions always have FIVE answer choices.

If a person has n friends, he can invite one or more of those friends to lunch in (2^n) - 1 ways.

Cheers,
Brent
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Junior | Next Rank: 30 Posts
Posts: 22
Joined: Sat Apr 19, 2014 5:24 am

by s91arvindh » Sun May 04, 2014 5:31 am
Thanks Brent !

These questions are given for in depth understanding the concept of permutation and combination.
Top
Join the discussion
Log in to postLogin with Googleuse password
QUOTE IN REPLY
Post new topic Post Reply
• Page 1 of 1