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

It is currently 18 Jun 2013, 16:53
Customize  |  Hide

Three brothers apply to a certain business school. The

  Question banks Downloads My Bookmarks Reviews  
Author Message
TAGS:
SVP
SVP
User avatar
Joined: 03 Feb 2003
Posts: 1680
Followers: 4

Kudos [?]: 16 [0], given: 0

Three brothers apply to a certain business school. The [#permalink] New post 29 Jun 2004, 06:48
00:00

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
Three brothers apply to a certain business school. The probability of the first one being admitted is 0.9; the second—0.5; the third—0.2. Find the probability that:

1) at least two are admitted
2) at least one is admitted
3) none is admitted
Senior Manager
Senior Manager
Joined: 26 Jan 2004
Posts: 428
Location: India
Followers: 1

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

GMAT Tests User
 [#permalink] New post 29 Jun 2004, 06:58
1) Atleast two --> 0.9*0.5+0.5*0.2+0.9*0.2+0.9*0.5*0.2 = 0.82
2) Atleast One --> 1 - None --> 1 - (1-0.9)*(1-0.5)(1-0.2) = 1 - 0.1*0.5*0.8 = 0.96
3) None (1-0.9)*(1-0.5)(1-0.2) = 0.04
Senior Manager
Senior Manager
Joined: 26 Jan 2004
Posts: 428
Location: India
Followers: 1

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

GMAT Tests User
 [#permalink] New post 29 Jun 2004, 07:43
Ya! sure about all three.

Why? is the OA different??
Senior Manager
Senior Manager
User avatar
Joined: 07 Oct 2003
Posts: 379
Location: Manhattan
Followers: 1

Kudos [?]: 2 [0], given: 0

GMAT Tests User
Re: PS: three brothers--probability [#permalink] New post 29 Jun 2004, 09:31
stolyar wrote:
Three brothers apply to a certain business school. The probability of the first one being admitted is 0.9; the second—0.5; the third—0.2. Find the probability that:

1) at least two are admitted
2) at least one is admitted
3) none is admitted


1) P(2 get in) + P(3 get in)=
.9(.5)*(1-.2)=.36
.9(.2)*(1-.5)=.09
.5(.2)*(1-.9)=.01
.36+.09+.01=.46 -->P2 get in
(mental check, 3C2=3 different ways to get 2 out of three)

P(3 get in) = .9(.5)(.2)=.09

P(2 get in) + P(3 get in) = .55

(from a quick glance, I think MBA forgot to multiply the probabilities of 2 get in by the probability of the 3rd person not getting in, hence his answer was of)

2) P (at least one gets in) = 1 - P(non are admitted)
1- (1-.9)(1-.5)(1-.2) = 1-.04=.96

3)P (none get in) = .04
Re: PS: three brothers--probability   [#permalink] 29 Jun 2004, 09:31
    Similar topics Author Replies Last post
Similar
Topics:
Popular new posts 1 Women Applying for Business School alienwannabe 21 14 Feb 2007, 11:37
New posts Working abroad and applying for business school miguel3072 3 17 Jan 2010, 22:36
New posts What are reasons for applying to a certain Business School? jakolik 7 07 Sep 2010, 05:30
New posts Actuaries applying to business school mbahopefull 2 21 Nov 2010, 11:20
New posts Applying for business schools in different continents timilon 3 15 Sep 2011, 21:29
Display posts from previous: Sort by

Three brothers apply to a certain business school. The

  Question banks Downloads My Bookmarks Reviews  


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®.