Results 1 to 2 of 2

Thread: Normal Distribution using probability

  1. #1
    Member
    Joined
    Nov 2015
    From
    Kolkata, India
    Posts
    100
    Thanks
    1

    Normal Distribution using probability

    A question says that "The distribution of lifetimes for a certain type of light bulb is normally distributed with mean 1000hours and standard deviation of 100hours. What is the 33rd percentile of the distribution of lifetimes?" How will I do it?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    12,807
    Thanks
    1920

    Re: Normal Distribution using probability

    You will need to look up on an inverse normal table what value of z gives an area of 0.33 and then get the x value from the formula $\displaystyle \begin{align*} z = \frac{x - \mu}{\sigma} \end{align*}$.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. probability normal distribution
    Posted in the Advanced Statistics Forum
    Replies: 1
    Last Post: Aug 16th 2010, 05:57 PM
  2. normal probability distribution
    Posted in the Statistics Forum
    Replies: 2
    Last Post: Nov 21st 2009, 09:50 PM
  3. probability...normal distribution
    Posted in the Statistics Forum
    Replies: 2
    Last Post: May 5th 2008, 12:04 PM
  4. Normal Distribution, Std. Dev., & Probability
    Posted in the Advanced Statistics Forum
    Replies: 3
    Last Post: Apr 29th 2008, 03:48 AM
  5. normal distribution and probability
    Posted in the Statistics Forum
    Replies: 4
    Last Post: Mar 13th 2007, 05:47 PM

Search Tags


/mathhelpforum @mathhelpforum