Math Help Forum

Math Help Forum Feed Site Feed

Go Back   Math Help Forum > University Math Help > Advanced Probability and Statistics
Reply
 
Thread Tools Display Modes
  #1  
Old July 19th, 2008, 12:34 AM
Junior Member
 
Join Date: Jun 2008
Posts: 29
Country:
Thanks: 4
Thanked 0 Times in 0 Posts
Myung is on a distinguished road
Default Discrete random variable help!

The average number of children per Spanish couples was 1.34 in 2005. Suppose that one Spanish couple is chosen randomly.

a. Find the probability that they have no children.
b. Find the probability that they have fewer children than the Spanish average.
c. Find the probability that thety have more children than the Spanish average.

I can't figure out what to do. This is all that is given.

Last edited by Myung; July 19th, 2008 at 12:58 AM.
Reply With Quote
Advertisement
 
  #2  
Old July 19th, 2008, 01:10 AM
CaptainBlack's Avatar
Grand Panjandrum
 
Join Date: Nov 2005
Location: South of England
Posts: 11,265
Country:
Thanks: 656
Thanked 3,585 Times in 2,887 Posts
CaptainBlack has a reputation beyond reputeCaptainBlack has a reputation beyond reputeCaptainBlack has a reputation beyond reputeCaptainBlack has a reputation beyond reputeCaptainBlack has a reputation beyond reputeCaptainBlack has a reputation beyond reputeCaptainBlack has a reputation beyond reputeCaptainBlack has a reputation beyond reputeCaptainBlack has a reputation beyond reputeCaptainBlack has a reputation beyond reputeCaptainBlack has a reputation beyond repute
Default

Quote:
Originally Posted by Myung View Post
The average number of children per Spanish couples was 1.34 in 2005. Suppose that one Spanish couple is chosen randomly.

a. Find the probability that they have no children.
b. Find the probability that they have fewer children than the Spanish average.
c. Find the probability that thety have more children than the Spanish average.

I can't figure out what to do. This is all that is given.
You don't have sufficient information to do this, you need to know the distribution for the number of children that a family has. Now it might be that you are supposed to assume a Poisson distribution, but that would be invalid.

RonL
__________________
Truth does not change because it is, or is not, believed by a majority of the people.

Giordano Bruno
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off
Forum Jump


All times are GMT -7. The time now is 07:34 PM.


Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.
SEO by vBSEO 3.2.0 ©2008, Crawlability, Inc.
©2005 - 2009 Math Help Forum


Math Help Forum is a community of maths forums with an emphasis on maths help in all levels of mathematics.
Register to post your math questions or just hang out and try some of our math games or visit the arcade.