Find all School-related info fast with the new School-Specific MBA Forum

It is currently 30 Oct 2014, 07:11

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Probability Question - Not from a book (No official answer)

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Intern
Intern
avatar
Joined: 16 Mar 2010
Posts: 42
Followers: 0

Kudos [?]: 8 [0], given: 39

Probability Question - Not from a book (No official answer) [#permalink] New post 07 May 2010, 08:42
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
Hey guys - long time lurker here and this is my first post.

My buddy at work was talking about how he plays a lottery where you pick 4 numbers and there is a drawing everyday, which got me thinking about it in terms of the gmat.

Probability of hitting the 4 numbers in order = 1 / 10^4 = 1/10,000 ?

But you can also "win the lottery" if you pick the 4 numbers correctly, not neccesarily in order.

I'm having a little trouble caluclating that number so if you all can help me understand that would be SUPER!

-Sameer
Kaplan Promo CodeKnewton GMAT Discount CodesGMAT Pill GMAT Discount Codes
Intern
Intern
avatar
Joined: 16 Mar 2010
Posts: 42
Followers: 0

Kudos [?]: 8 [0], given: 39

Re: Probability Question - Not from a book (No official answer) [#permalink] New post 10 May 2010, 05:34
Guys come on!!

I thought we were friends!!!!!
Senior Manager
Senior Manager
avatar
Joined: 25 Jun 2009
Posts: 313
Followers: 2

Kudos [?]: 80 [0], given: 6

Re: Probability Question - Not from a book (No official answer) [#permalink] New post 10 May 2010, 06:07
sameermunshi wrote:
Hey guys - long time lurker here and this is my first post.

My buddy at work was talking about how he plays a lottery where you pick 4 numbers and there is a drawing everyday, which got me thinking about it in terms of the gmat.

Probability of hitting the 4 numbers in order = 1 / 10^4 = 1/10,000 ?

But you can also "win the lottery" if you pick the 4 numbers correctly, not neccesarily in order.

I'm having a little trouble caluclating that number so if you all can help me understand that would be SUPER!

-Sameer

Okay, even though I am not an expert but let me give a shot to this one...!

So 4 numbers to choose from ..

so the probability for the 1st number on our lottery ( 4/10 ) because we have 4 numbers to choose from-- assuming we are talking about digits(0-9) here

for 2nd number it should 3/10 and similarly for 3rd number 2/10

So final probablity = \frac{(4 *3*2*1)}{10*10*10*10}

Cheers,
Intern
Intern
avatar
Joined: 16 Mar 2010
Posts: 42
Followers: 0

Kudos [?]: 8 [0], given: 39

Re: Probability Question - Not from a book (No official answer) [#permalink] New post 10 May 2010, 11:12
Thanks Nitish!

So quick question:

if 4*3*2*1 /10*10*10*10 = Prob of picking 4 numbers (order doesnt matter) out of 10

what would 4*4*4*4 / 10*10*10*10 mean? ?

Anyone else have any input?

Appreciate it!!
nitishmahajan wrote:
sameermunshi wrote:
Hey guys - long time lurker here and this is my first post.

My buddy at work was talking about how he plays a lottery where you pick 4 numbers and there is a drawing everyday, which got me thinking about it in terms of the gmat.

Probability of hitting the 4 numbers in order = 1 / 10^4 = 1/10,000 ?

But you can also "win the lottery" if you pick the 4 numbers correctly, not neccesarily in order.

I'm having a little trouble caluclating that number so if you all can help me understand that would be SUPER!

-Sameer

Okay, even though I am not an expert but let me give a shot to this one...!

So 4 numbers to choose from ..

so the probability for the 1st number on our lottery ( 4/10 ) because we have 4 numbers to choose from-- assuming we are talking about digits(0-9) here

for 2nd number it should 3/10 and similarly for 3rd number 2/10

So final probablity = \frac{(4 *3*2*1)}{10*10*10*10}

Cheers,
Senior Manager
Senior Manager
avatar
Joined: 25 Jun 2009
Posts: 313
Followers: 2

Kudos [?]: 80 [0], given: 6

Re: Probability Question - Not from a book (No official answer) [#permalink] New post 10 May 2010, 11:27
sameermunshi wrote:
Thanks Nitish!

So quick question:

if 4*3*2*1 /10*10*10*10 = Prob of picking 4 numbers (order doesnt matter) out of 10

what would 4*4*4*4 / 10*10*10*10 mean? ?

Anyone else have any input?

Appreciate it!!
nitishmahajan wrote:
sameermunshi wrote:
Hey guys - long time lurker here and this is my first post.

My buddy at work was talking about how he plays a lottery where you pick 4 numbers and there is a drawing everyday, which got me thinking about it in terms of the gmat.

Probability of hitting the 4 numbers in order = 1 / 10^4 = 1/10,000 ?

But you can also "win the lottery" if you pick the 4 numbers correctly, not neccesarily in order.

I'm having a little trouble caluclating that number so if you all can help me understand that would be SUPER!

-Sameer

Okay, even though I am not an expert but let me give a shot to this one...!

So 4 numbers to choose from ..

so the probability for the 1st number on our lottery ( 4/10 ) because we have 4 numbers to choose from-- assuming we are talking about digits(0-9) here

for 2nd number it should 3/10 and similarly for 3rd number 2/10

So final probablity = \frac{(4 *3*2*1)}{10*10*10*10}

Cheers,


Well, Say for e.g the case would have been that we need to pick 4 numbers in any order and at any place holder.

For e.g winning lottery number would have been 4678 and so the condition would have been something like 4 numbers
any order like 4468 or may be even 6777 ( I mean to say any number can fit any where even with repetition then

\frac{4*4*4*4}{10*10*10*10}

Would have fit the bill...!

Cheers
Senior Manager
Senior Manager
User avatar
Joined: 21 Jul 2009
Posts: 367
Schools: LBS, INSEAD, IMD, ISB - Anything with just 1 yr program.
Followers: 14

Kudos [?]: 101 [0], given: 22

Re: Probability Question - Not from a book (No official answer) [#permalink] New post 10 May 2010, 12:18
Is my understanding wrong??

You have 10 digits from 0 to 9 inclusive. You are selecting one number from the 10 for every place, thus you select 4 times to get a four digit number - (10C1)^4 = 10 * 10 * 10 * 10 = 10000.

All possible 4 digit numbers - 9 * 10 * 10 * 10 = 9000 (have to give up 0 for the first spot).

Probability of choosing a 4 digit number from the entire lot = 10000/9000 = 10/9 > 1.

Is this even possible? what am I doing wrong with the question??
_________________

I am AWESOME and it's gonna be LEGENDARY!!!

Re: Probability Question - Not from a book (No official answer)   [#permalink] 10 May 2010, 12:18
    Similar topics Author Replies Last post
Similar
Topics:
2 700 + level Official questions Collections with Answers ZeroIQ 0 30 Jul 2014, 08:15
2 Experts publish their posts in the topic Probability question from Kaplan book Rtr6262 3 16 Mar 2014, 17:12
Experts publish their posts in the topic practice questions from Official Guide adequate for prep? mkolympic 4 09 Feb 2012, 22:58
4 Why is the official answer the best answer? niheil 7 19 Oct 2010, 19:59
1 Help - questions from the official GMAT prep test Romaster 3 17 Aug 2010, 01:48
Display posts from previous: Sort by

Probability Question - Not from a book (No official answer)

  Question banks Downloads My Bookmarks Reviews Important topics  


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

Powered by phpBB © phpBB Group and phpBB SEO

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®.