My Math Forum  

Go Back   My Math Forum > High School Math Forum > Probability and Statistics

Probability and Statistics Basic Probability and Statistics Math Forum


Reply
 
LinkBack Thread Tools Display Modes
May 10th, 2010, 10:18 PM   #1
Newbie
 
Joined: May 2010

Posts: 1
Thanks: 0

Probability Problem.Please help

A lot contains 20 articles.The probability that the lot contains exactly 2 defective articles is 0.4 and that it contains exactly 3 defective articles is 0.6.Articles are drawn from the lot at random 1 by 1 without replacement and tested till all the defective articles are found.What is the probability that this procedure ends at the 12th testing?
adiptadatta is offline  
 
May 11th, 2010, 07:46 AM   #2
Senior Member
 
Joined: Apr 2008

Posts: 435
Thanks: 0

Re: Probability Problem.Please help

I have a small question. Presume, for a moment, that we happen to choose a lot which has 2 defective articles. Then, as we don't know whether we're in a lot with 2 or 3 defective articles, we must test all 20 before we realize that there is no third defective article... unless I am missing an assumption.
jason.spade is offline  
Reply

  My Math Forum > High School Math Forum > Probability and Statistics

Tags
probability, problemplease



Search tags for this page
Click on a term to search for related topics.
Thread Tools
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
Probability Problem / Insurance problem bsjmath Advanced Statistics 2 March 1st, 2014 03:50 PM
Probability problem ystiang Advanced Statistics 1 February 13th, 2014 05:27 PM
probability problem Vasia Probability and Statistics 0 December 15th, 2012 02:48 AM
Probability problem halloweengrl23 Advanced Statistics 3 March 23rd, 2012 03:27 AM
Help with probability problem! indian Algebra 0 February 21st, 2008 05:10 PM





Copyright © 2018 My Math Forum. All rights reserved.