Live GMAT classes with Target Test Prep start Nov 21 and Nov 22. First class free.

See classes
Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep

Target Test Prep was voted #1 Best Test Prep in the 2026 Newsweek Readers’ Choice™ Awards.

★★★★★5.0563 reviews
GMATLiveTeachStarts Nov 22
Josh Braslow, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Josh Braslow, 20+ years in test prep

Nov 22 · Josh Braslow
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes + 6 months of TTP OnDemand
  • Attend the first class for free
  • Every class is recorded, so you never fall behind
View classes & enroll
Limited seats availableTarget Test Prep
EALiveTeachOnDemandStart anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

EXECUTIVE ASSESSMENT

with

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll Start free 5-day trial
Limited cohort · enrollment openTrial includes full course accessTarget Test Prep
GMATOnDemandStart anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions
Start free 5-day trial
Read 563 reviewsTarget Test Prep

Car with seven options

Expert replies
Post new topic Post Reply
Subscribe topic
Previous Topic Next Topic

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16206
Joined: Mon Dec 08, 2008 6:26 pmFollowed by: 1268 members
Location: Vancouver, BC
Thanked: 5254 times
GMAT Score:770
by Brent@GMATPrepNow » Sun Jan 18, 2009 9:13 am
A certain make of car has the following seven options: air conditioning, sunroof, DVD player, CD changer, leather upholstery, tinted windows and cruise control. A person ordering this make of car has how many different combinations from which to choose?
(A) 49
(B) 56
(C) 98
(D) 128
(E) 840
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Join the discussion
Source: — Problem Solving |
User avatar
Site Admin
Posts: 2567
Joined: Thu Jan 01, 2009 10:05 amFollowed by: 550 members
Thanked: 712 times
GMAT Score:770

by DanaJ » Sun Jan 18, 2009 9:16 am
I'd go with 7! = 840, but I may be very wrong...
Top
Join the discussion

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16206
Joined: Mon Dec 08, 2008 6:26 pmFollowed by: 1268 members
Location: Vancouver, BC
Thanked: 5254 times
GMAT Score:770

by Brent@GMATPrepNow » Sun Jan 18, 2009 9:33 am
Sorry, it's not E.
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Join the discussion
User avatar
Site Admin
Posts: 2567
Joined: Thu Jan 01, 2009 10:05 amFollowed by: 550 members
Thanked: 712 times
GMAT Score:770

by DanaJ » Sun Jan 18, 2009 9:37 am
You're right... I'm so dumb... It's 0C7 + 1C7 + ... + 7C7 = 2^7 = 128. Sorry...
Last edited by DanaJ on Sun Jan 18, 2009 9:45 am, edited 1 time in total.
Top
Join the discussion

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 16206
Joined: Mon Dec 08, 2008 6:26 pmFollowed by: 1268 members
Location: Vancouver, BC
Thanked: 5254 times
GMAT Score:770

by Brent@GMATPrepNow » Sun Jan 18, 2009 9:42 am
128 it is.
One option is to consider 8 different cases (get zero options, get 1 option, get 2 options, get 3 options and so on). So we get the total combinations as 7C0 + 7C1 + 7C2 + . . . + 7C6 + 7C7
This is a lot of work.

The other strategy is to break this task into seven stages:
1) Choose whether or not to get air conditioning, sunroof, DVD player
2) Choose whether or not to get air the sunroof
. . .
7) Choose whether or not to get cruise control

Each stage can be accomplished in 2 ways.
So, by the Fundamental Counting Principle, the total number of ways to accomplish all 7 stages is 2x2x2x2x2x2x2 = 128

In general, the sum nC0 + nC1 + nC2 + . . . nCn = 2^n
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top
Join the discussion
User avatar
Site Admin
Posts: 2567
Joined: Thu Jan 01, 2009 10:05 amFollowed by: 550 members
Thanked: 712 times
GMAT Score:770

by DanaJ » Sun Jan 18, 2009 9:45 am
Hmm... I messed up the C's over there... because this is not standard notation in my country... Over here it's smth like both numbers are in front of the C, the bigger one on the bottom and the smaller one on top... I guess I should have written 7C0 + 7C1 + etc...
Top
Join the discussion
Legendary Member
Posts: 512
Joined: Mon Jun 18, 2012 11:31 pmFollowed by: 20 members
Thanked: 42 times

by sana.noor » Tue Jul 30, 2013 11:41 pm
D it should be as we have 2 options for every 7 options 2.2.2.2.2.2.2 = 128.
Work hard in Silence, Let Success make the noise.

If you found my Post really helpful, then don't forget to click the Thank/follow me button. :)
Top
Join the discussion