Last visit was: 25 Apr 2024, 04:43 It is currently 25 Apr 2024, 04:43

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
User avatar
Intern
Intern
Joined: 10 Oct 2008
Posts: 46
Own Kudos [?]: 380 [32]
Given Kudos: 0
Send PM
Most Helpful Reply
User avatar
Manager
Manager
Joined: 14 Oct 2008
Posts: 70
Own Kudos [?]: 222 [11]
Given Kudos: 0
Send PM
General Discussion
User avatar
Manager
Manager
Joined: 27 May 2008
Posts: 70
Own Kudos [?]: 278 [0]
Given Kudos: 0
Send PM
User avatar
Intern
Intern
Joined: 26 Sep 2008
Posts: 7
Own Kudos [?]: 8 [2]
Given Kudos: 0
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
2
Bookmarks
my ans is D but it's not 4!
let's assume the signal is ABC
so A has 4 cases
B has 3 cases
C has 2 cases
so there are 4x3x2=24
User avatar
Director
Director
Joined: 17 Jun 2008
Posts: 614
Own Kudos [?]: 444 [4]
Given Kudos: 0
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
4
Kudos
Another way to look at it.

This is a permutation problem and hence answer will be 4P3 = 24.
Senior Manager
Senior Manager
Joined: 24 Nov 2015
Posts: 408
Own Kudos [?]: 125 [1]
Given Kudos: 231
Location: United States (LA)
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
1
Kudos
Consider a flagpole with 3 vertical slots for flags
As we have to select different flags we can do as follows
topmost flag can be paced in 4 ways
middle flag can be placed in 3 ways
bottom most flag can be placed in 2 ways
(order doesn't matter the selection matters)
Total ways = 4 * 3 * 2 = 24 ways
correct answer - D
Retired Moderator
Joined: 19 Mar 2014
Posts: 817
Own Kudos [?]: 969 [2]
Given Kudos: 199
Location: India
Concentration: Finance, Entrepreneurship
GPA: 3.5
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
2
Kudos
Jcpenny wrote:
Each signal that a certain ship can make is comprised of 3 different flags hanging vertically in a particular order. How many unique signals can be made by using 4 different flags?

A. 10
B. 12
C. 20
D. 24
E. 36


As the order matters:

4 (First Flag) * 3 (Second Flag) * 2 (Third Flag)

24

Hence, Answer is D
Intern
Intern
Joined: 06 Feb 2017
Posts: 6
Own Kudos [?]: 0 [0]
Given Kudos: 9
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
Can anyone please share any theory topic related to this problem I am not getting it
TIA
Retired Moderator
Joined: 19 Mar 2014
Posts: 817
Own Kudos [?]: 969 [1]
Given Kudos: 199
Location: India
Concentration: Finance, Entrepreneurship
GPA: 3.5
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
1
Bookmarks
Business Analyst wrote:
Can anyone please share any theory topic related to this problem I am not getting it
TIA



Here you will find all the theory topics explained very well.

https://gmatclub.com/forum/gmat-math-bo ... 30609.html
Senior Manager
Senior Manager
Joined: 28 Jun 2015
Posts: 250
Own Kudos [?]: 293 [1]
Given Kudos: 47
Concentration: Finance
GPA: 3.5
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
1
Kudos
One signal has 3 different flags. No. of unique signals that can be made = 3*2*1 = 6.
No. of ways of choosing 3 flags from 4 flags = 4c3 = 4.

No. of signals that can be made = 24. Ans - D.
Target Test Prep Representative
Joined: 04 Mar 2011
Status:Head GMAT Instructor
Affiliations: Target Test Prep
Posts: 3043
Own Kudos [?]: 6272 [1]
Given Kudos: 1646
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
1
Kudos
Expert Reply
Jcpenny wrote:
Each signal that a certain ship can make is comprised of 3 different flags hanging vertically in a particular order. How many unique signals can be made by using 4 different flags?

A. 10
B. 12
C. 20
D. 24
E. 36


The number of unique signals is 4P3 = 4 x 3 x 2 = 24.

Answer: D
Math Revolution GMAT Instructor
Joined: 16 Aug 2015
Posts: 10161
Own Kudos [?]: 16595 [1]
Given Kudos: 4
GMAT 1: 760 Q51 V42
GPA: 3.82
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
1
Bookmarks
Expert Reply
Flags available : 4
Signal has: 3 flags

For first flag: 4 choices.
Second flag:3 choices
Third flag: 2 choices

Overall: 4 * 3 * 2 = 24 ways

Answer D
Intern
Intern
Joined: 29 May 2020
Posts: 2
Own Kudos [?]: 0 [0]
Given Kudos: 19
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
A (n,m) = n!/ (n-m)!
A (4, 3) = 4!/ (4-3) ! = 4! = 24
Answer is D
VP
VP
Joined: 11 Aug 2020
Posts: 1262
Own Kudos [?]: 201 [0]
Given Kudos: 332
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
Combinations + Permutations.

4C3 x 3! = 4 x 6 = 24.

Answer is D.
User avatar
Non-Human User
Joined: 09 Sep 2013
Posts: 32667
Own Kudos [?]: 821 [0]
Given Kudos: 0
Send PM
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
GMAT Club Bot
Re: Each signal that a certain ship can make is comprised of 3 different [#permalink]
Moderators:
Math Expert
92912 posts
Senior Moderator - Masters Forum
3137 posts

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