Last visit was: 24 Apr 2024, 00:14 It is currently 24 Apr 2024, 00:14

Close
GMAT Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
SORT BY:
Date
Tags:
Show Tags
Hide Tags
Intern
Intern
Joined: 03 Feb 2017
Posts: 3
Own Kudos [?]: 22 [17]
Given Kudos: 5
Send PM
Tutor
Joined: 12 Oct 2010
Status:GMATH founder
Posts: 893
Own Kudos [?]: 1352 [1]
Given Kudos: 56
Send PM
e-GMAT Representative
Joined: 04 Jan 2015
Posts: 3726
Own Kudos [?]: 16832 [1]
Given Kudos: 165
Send PM
GMAT Club Legend
GMAT Club Legend
Joined: 03 Oct 2013
Affiliations: CrackVerbal
Posts: 4946
Own Kudos [?]: 7625 [3]
Given Kudos: 215
Location: India
Send PM
Re: Committee X has 4 members, committee Y has 5 members, and these commit [#permalink]
3
Kudos
Top Contributor
This is a question of choices and hence is a question on combinations. Order does not matter.

\(^nC_r = \frac{n!}{(n-r)!*r!}\)

Important values to remember are that \(^nC_1 = n\), \(^nC_n = 1\) and \(^nC_0 = 1\)


Committee X has 4 members: Choosing one out of 4 = \(^4C_1 = 4\)

Committee Y has 5 members: Choosing one out of 5 = \(^5C_1 = 5\)


Since we need to ensure that one of each has to be chosen to create a task force, the even is not completed until one of each is chosen. Therefore we multiply the 2 values. The total possibilities = 4 * 5 = 20


Option D

Arun Kumar
Director
Director
Joined: 29 Apr 2019
Status:Learning
Posts: 751
Own Kudos [?]: 583 [0]
Given Kudos: 49
Send PM
Re: Committee X has 4 members, committee Y has 5 members, and these commit [#permalink]
Correct option D - 20 [4C1 x 5C1 = 4x5 = 20]
Intern
Intern
Joined: 16 Apr 2023
Posts: 38
Own Kudos [?]: [0]
Given Kudos: 107
Location: Canada
Send PM
Re: Committee X has 4 members, committee Y has 5 members, and these commit [#permalink]
Isn't there double counting happening here? i.e. we are counting picking member 1 from committee x and member 1 from committee y, and then again we are counting picking member 1 from committee y and member 1 from committee x?
Intern
Intern
Joined: 24 Aug 2023
Posts: 10
Own Kudos [?]: 0 [0]
Given Kudos: 50
Location: United States (NY)
Send PM
Re: Committee X has 4 members, committee Y has 5 members, and these commit [#permalink]
kelly_jacques wrote:
Isn't there double counting happening here? i.e. we are counting picking member 1 from committee x and member 1 from committee y, and then again we are counting picking member 1 from committee y and member 1 from committee x?


Hi! Actually, no. Please, read the best explanation above, which provides the number of combinations. This means that possible repetitions are excluded.
Also, we use the 4 times 5 because it is a condition to find a max possible variety of 2 combinations at once (using AND as a multiplicator).
GMAT Club Bot
Re: Committee X has 4 members, committee Y has 5 members, and these commit [#permalink]
Moderators:
Math Expert
92883 posts
Senior Moderator - Masters Forum
3137 posts

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne