GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 26 Sep 2018, 05:53

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

Bill is renting DVDs from the video store. He must choose three DVDs

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Senior Manager
Senior Manager
User avatar
P
Joined: 12 Feb 2015
Posts: 436
Premium Member CAT Tests
Bill is renting DVDs from the video store. He must choose three DVDs  [#permalink]

Show Tags

New post 25 Jun 2018, 08:32
00:00
A
B
C
D
E

Difficulty:

  25% (medium)

Question Stats:

69% (01:07) correct 31% (00:52) wrong based on 63 sessions

HideShow timer Statistics

Bill is renting DVDs from the video store. He must choose three DVDs from a list of eight new releases and then decide in what order to watch them. How many different schedules of DVDs can he create, if he cannot watch the same movie more than once?

(A) 24
(B) 56
(C) 72
(D) 336
(E) 512

_________________

"Please hit :thumbup: +1 Kudos if you like this post" :student_man:

_________________
Manish :geek:

"Only I can change my life. No one can do it for me"

Math Expert
User avatar
V
Joined: 02 Aug 2009
Posts: 6815
Re: Bill is renting DVDs from the video store. He must choose three DVDs  [#permalink]

Show Tags

New post 25 Jun 2018, 08:39
CAMANISHPARMAR wrote:
Bill is renting DVDs from the video store. He must choose three DVDs from a list of eight new releases and then decide in what order to watch them. How
many different schedules of DVDs can he create, if he cannot watch the same movie more than once?
(A) 24
(B) 56
(C) 72
(D) 336
(E) 512


It is permutation question.. 8P3=8!/5!=8*7*6=56*6=336

Or you can work on combinations..

First find the possible combinations..
8C5=8!/(5!3!)=8*7*6/6=8*7=56
But these 3 can be arranged in 3! Ways
So total ways =56*3!=336

D
_________________

1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372
2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html
3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html


GMAT online Tutor

Intern
Intern
User avatar
B
Status: Prep Mode
Joined: 16 Jan 2015
Posts: 17
Location: India
WE: Programming (Computer Software)
Re: Bill is renting DVDs from the video store. He must choose three DVDs  [#permalink]

Show Tags

New post 25 Jun 2018, 09:43
Total no of DVDs = 8
No of DVDs Bill has to select at a time = 3

He can selecting 3 from 8 in \(8c3\) ways.

Selected 3 DVDs can be seen in 3! ways.

So total no of ways = \(8c3\) * 3! = (\(\frac{8!}{3!*5!}\)) * 3! = 8*7*6 = 336
Target Test Prep Representative
User avatar
G
Status: Founder & CEO
Affiliations: Target Test Prep
Joined: 14 Oct 2015
Posts: 3527
Location: United States (CA)
Re: Bill is renting DVDs from the video store. He must choose three DVDs  [#permalink]

Show Tags

New post 26 Jun 2018, 17:55
CAMANISHPARMAR wrote:
Bill is renting DVDs from the video store. He must choose three DVDs from a list of eight new releases and then decide in what order to watch them. How many different schedules of DVDs can he create, if he cannot watch the same movie more than once?

(A) 24
(B) 56
(C) 72
(D) 336
(E) 512


Because the order in which Bill watches the DVDs is important, we use permutations. The number of ways to select and watch 3 DVD’s is 8P3 = 8!/(8 - 3)! = 8!/5! = 8 x 7 x 6 = 336.

Answer: D
_________________

Scott Woodbury-Stewart
Founder and CEO

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Manager
Manager
avatar
B
Joined: 08 Sep 2016
Posts: 116
Bill is renting DVDs from the video store. He must choose three DVDs  [#permalink]

Show Tags

New post 28 Jun 2018, 14:33
The key word in this question is order. For this type of question, use Permutation.

A helpful hint I use when doing this type of problem is to think of the made up word "POM". I think of it as an acronym I made up to remind me to use Permutation when order matters:
POM = Permutation when Order Matters.

8P3 = 8!/(8-3)! = 8!/5! = 336

Answer D
GMAT Club Bot
Bill is renting DVDs from the video store. He must choose three DVDs &nbs [#permalink] 28 Jun 2018, 14:33
Display posts from previous: Sort by

Bill is renting DVDs from the video store. He must choose three DVDs

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  

Events & Promotions

PREV
NEXT


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

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

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.