Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Binomial what now.

  1. Feb 26, 2010 #1
    can anyone help with this:

     
  2. jcsd
  3. Feb 26, 2010 #2
    Go through the first part of the problem first. You know N=20. Then try n=0, 1, and 2 using what you know about calculating probabilities using binomial distribution.
    It states 5% of all components are defective. So how many in a sample of 20 are defective? What is the probabilities of having 0 defectives? How about 1 and 2?
    Here is a link in case: http://mathworld.wolfram.com/BinomialDistribution.html
     
  4. Feb 26, 2010 #3
    thats the problem, i have no clue how to do binomial and when ever i look at it online it just blags my head, anyone help me with some step by step instructions on working it out?
     
  5. Feb 26, 2010 #4
    Here is a link: http://www.intmath.com/Counting-probability/12_Binomial-probability-distributions.php
    It gives a description of the formula and examples, complete with solutions.

    Once you have read through the page, move on to your question. It is a lot like the problems on the page. The important step is to identify the variables. Try (i) - the probably of 0 being the number of defective samples. Thus x=0. You are taking 20 total samples, so n=20. You are also given the probability that 5% are defective. Now it is a matter of plugging everything in the formula.
     
    Last edited: Feb 26, 2010
  6. Feb 27, 2010 #5

    Redbelly98

    User Avatar
    Staff Emeritus
    Science Advisor
    Homework Helper

    Moderator's note: thread moved from "Set Theory, Logic, Probability, Statistics"
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook