Results 1 to 3 of 3

Math Help - Probability ???

  1. #1
    Newbie
    Joined
    Oct 2008
    Posts
    8

    Smile Probability ???

    Probabaility that a pen manufactured by a company will be defective is 1/10.If 12 such pen are manufacturd,find yhe probability for?


    1. exactly two will be defective
    2. at least two will be defective
    3.none will be defective

    THANKS !!!!!!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by Sameera View Post
    Probabaility that a pen manufactured by a company will be defective is 1/10.If 12 such pen are manufacturd,find yhe probability for?


    1. exactly two will be defective
    2. at least two will be defective
    3.none will be defective

    THANKS !!!!!!
    Are you familiar with the binomial distribution?

    Let X be the random variable number of manufactured pens that are defective.

    X ~ Binomial(n = 12, p = 1/10).

    Calculate:

    1. \Pr(X = 2)

    2. \Pr(X \geq 2) = 1 - \Pr(X \leq 1)

    3. \Pr(X = 0).
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Kai
    Kai is offline
    Junior Member
    Joined
    Apr 2008
    Posts
    59
    Quote Originally Posted by Sameera View Post
    Probabaility that a pen manufactured by a company will be defective is 1/10.If 12 such pen are manufacturd,find yhe probability for?


    1. exactly two will be defective
    2. at least two will be defective
    3.none will be defective

    THANKS !!!!!!
    Hi,

    Make use of binomial distribution

    X~B(n,p) where n is the number of pens(12 in ur case) and p is the probability of success ( for u case, its to get a defective pen which is 0.1)

    Now calculate P(X=2) and so on...

    Hope it helps
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 10
    Last Post: January 21st 2011, 12:47 PM
  2. Replies: 3
    Last Post: May 29th 2010, 08:29 AM
  3. fundamental in probability & convergence with probability 1
    Posted in the Advanced Statistics Forum
    Replies: 3
    Last Post: February 23rd 2010, 10:58 AM
  4. Replies: 1
    Last Post: February 18th 2010, 02:54 AM
  5. Replies: 3
    Last Post: December 15th 2009, 07:30 AM

Search Tags


/mathhelpforum @mathhelpforum