Results 1 to 4 of 4

Math Help - posibilitys

  1. #1
    Junior Member
    Joined
    Mar 2009
    Posts
    34

    posibilitys

    For year 8 students, 20% have a shoe size greater than 10.5, but 95% have a shoe size less than 11.5. What is the chance of a year 8 student having a shoe size:
    a. less than or equal to 10.5
    b.11.5 or greater
    c.between 10.5 and 11.5


    i really dont know how to find the chances, please can someone explain to me how to do it??
    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 kl050196 View Post
    For year 8 students, 20% have a shoe size greater than 10.5, but 95% have a shoe size less than 11.5. What is the chance of a year 8 student having a shoe size:
    a. less than or equal to 10.5
    b.11.5 or greater
    c.between 10.5 and 11.5


    i really dont know how to find the chances, please can someone explain to me how to do it??
    You're given \Pr(X > 10.5) = 0.2 and \Pr(X < 11.5) = 0.95.

    a. \Pr(X \leq 10.5) = 1 - \Pr(X > 10.5).

    b. \Pr(X \geq 11.5) = 1 - \Pr(X < 11.5).

    c. \Pr(10.5  < X < 11.5) = \Pr(X  < 11.5) - \Pr(X < 10.5).
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Mar 2009
    Posts
    34
    Quote Originally Posted by mr fantastic View Post
    You're given \Pr(X > 10.5) = 0.2 and \Pr(X < 11.5) = 0.95.

    a. \Pr(X \leq 10.5) = 1 - \Pr(X > 10.5).

    b. \Pr(X \geq 11.5) = 1 - \Pr(X < 11.5).

    c. \Pr(10.5  < X < 11.5) = \Pr(X  < 11.5) - \Pr(X < 10.5).

    i dont get it
    Follow Math Help Forum on Facebook and Google+

  4. #4
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by kl050196 View Post
    i dont get it
    Be specific - what don't you get?
    Follow Math Help Forum on Facebook and Google+

Search Tags


/mathhelpforum @mathhelpforum