Results 1 to 2 of 2

Math Help - data managment help!

  1. #1
    Newbie
    Joined
    Nov 2008
    Posts
    1

    data managment help!

    hi I was wondering if anyone could help me figure this question out I think it is binomial distibution but I'm honestly not sure

    If 20 coins are dropped on a table. what is the probability ( to three decimal places ) that
    a) exactly 12 coins are heads
    b) At least 12 coins are heads
    if anyone could help me that would be great!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Newbie
    Joined
    Oct 2008
    Posts
    14
    It is in fact the binomial distribution because the trials are independent of each other and you are counting the number of successes with a given number of trials.

    For (a),
    Let X be the number of heads.
    P(X=12) = (20 C 12)*(0.5^12)*(0.5^8)

    I'll let you do the computation yourself.

    For (b),
    Note from (a), the binomial distribution will always be a comination multiplied by 0.5^20
    P(X>=12) = P(X=12)+P(X=13)+P(X=14)+...+P(X=20)
    For each probability, just sub in the X value (eg. P(X=13) = (20 C X)*(0.5^20)

    Once again, I'll leave the computation up to you.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Interpolating z(x,y) data point from 4 data points (rectangular)?
    Posted in the Advanced Applied Math Forum
    Replies: 2
    Last Post: June 20th 2011, 07:04 PM
  2. Replies: 2
    Last Post: July 6th 2010, 07:33 PM
  3. extracting data from matlab data structures
    Posted in the Math Software Forum
    Replies: 4
    Last Post: May 19th 2010, 05:12 PM
  4. Data help
    Posted in the Statistics Forum
    Replies: 1
    Last Post: January 21st 2008, 08:33 PM
  5. [SOLVED] Financial Managment Problems
    Posted in the Business Math Forum
    Replies: 1
    Last Post: October 8th 2006, 12:35 AM

Search Tags


/mathhelpforum @mathhelpforum