Thread: Discrete random variable help!
View Single Post
  #2  
Old July 19th, 2008, 01:10 AM
CaptainBlack's Avatar
CaptainBlack CaptainBlack is offline
Grand Panjandrum
  
Join Date: Nov 2005
Location: South of England
Posts: 11,379
Country:
Thanks: 667
Thanked 3,619 Times in 2,916 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