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

Redeem

What is the number of different committees of 4 people that can be selected from a group of 10 people?

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Source: — Problem Solving |
Legendary Member
Posts: 2499
Joined: Sun Oct 29, 2017 2:04 pm
Followed by:6 members

Re: What is the number of different committees of 4 people that can be selected from a group of 10 people?

by swerve » Thu Jan 30, 2020 2:59 pm
BTGmoderatorDC wrote: ↑
Wed Jan 29, 2020 4:59 pm
 What is the number of different committees of 4 people that can be selected from a group of 10 people?

A. 20

B. 40

C. 80

D. 120

E. 210



OA E

Source: GMAT Prep
We are to determine the number of 4 member committees that can be formed from 10 people. This is simple combination problem since order is not important here.

So, Number of ways = 10C4 = 210.

Therefore, the correct answer is __E__
Top

GMAT/MBA Expert

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

Re: What is the number of different committees of 4 people that can be selected from a group of 10 people?

by Brent@GMATPrepNow » Fri Jan 31, 2020 6:57 am
BTGmoderatorDC wrote: ↑
Wed Jan 29, 2020 4:59 pm
 What is the number of different committees of 4 people that can be selected from a group of 10 people?

A. 20

B. 40

C. 80

D. 120

E. 210



OA E

Source: GMAT Prep
Since the order in which we select the committee members does not matter, we can use combinations to solve this question

We can select 4 people from 10 people in 10C4 ways
10C4 = (10)(9)(8)(7)/(4)(3)(2)(1)
= (10)(9)(7)/(3)(1)
= (10)(3)(7)
= 210

Answer: E

ASIDE: Here's a video on how to reduce your calculations when evaluating combinations like 10C4: https://www.gmatprepnow.com/module/gmat ... /video/789
Brent Hanneson - Creator of GMATPrepNow.com
Image
Top

GMAT/MBA Expert

User avatar
GMAT Instructor
Posts: 8086
Joined: Sat Apr 25, 2015 10:56 am
Location: Los Angeles, CA
Thanked: 43 times
Followed by:29 members

Re: What is the number of different committees of 4 people that can be selected from a group of 10 people?

by Scott@TargetTestPrep » Sun Feb 02, 2020 12:39 pm
BTGmoderatorDC wrote: ↑
Wed Jan 29, 2020 4:59 pm
 What is the number of different committees of 4 people that can be selected from a group of 10 people?

A. 20

B. 40

C. 80

D. 120

E. 210



OA E

Source: GMAT Prep
The number of committees that can be selected is:

10C4 = 10! / (4! x 6!) = (10 x 9 x 8 x 7) / (4 x 3 x 2) = 5 x 3 x 2 x 7 = 210.

Answer: E

Scott Woodbury-Stewart
Founder and CEO
[email protected]

Image

See why Target Test Prep is rated 5 out of 5 stars on BEAT the GMAT. Read our reviews

ImageImage
Top
Post new topic Post Reply
• Page 1 of 1