Results 1 to 2 of 2

Math Help - [SOLVED] Finding the Area under the Curve.

  1. #1
    Newbie
    Joined
    Mar 2009
    Posts
    1

    Exclamation [SOLVED] Finding the Area under the Curve.

    Please help me with this problem. I have a test in the class tomorrow. I already found the height of the distribution by using 1 divided by the total width of the distribution and got 0.5, but from there I'm stuck. Please help.

    This is the problem:

    A statistics professor plans classes so carefully that the lengths of her classes are uniformly distributed between 50.0 and 52.0 minutes. Find the probability that a given period runs less than 50.75 minutes.

    Thank you for any help.


    -Sarah
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor matheagle's Avatar
    Joined
    Feb 2009
    Posts
    2,763
    Thanks
    5
    It seems that you are looking at a U(50,52) random variable.
    Since the length is 52-50=2, the height of this constant density must be .5.
    That's because the area must be one.
    So, f(x)=.5 on 50<x<52 and zero otherwise.
    You can integrate, but its just a rectangle.
    The probability that X is less than 50.75 is the area under f(x) from 50 to 50.75.
    That length is .75 or 3/4 and you multiply that by the height of .5 or 1/2
    to give you the probability of that event, 3/8.

    But why do you say that this is a normal random variable?
    I would then say the mean is 51, but I have no idea what the standard deviation is.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] Finding area of curve?
    Posted in the Calculus Forum
    Replies: 2
    Last Post: August 9th 2011, 05:55 PM
  2. Finding area of curve....
    Posted in the Calculus Forum
    Replies: 1
    Last Post: May 14th 2010, 02:38 PM
  3. [SOLVED] Finding the area of the curve
    Posted in the Calculus Forum
    Replies: 2
    Last Post: April 29th 2010, 10:40 AM
  4. Finding the area under the curve?
    Posted in the Statistics Forum
    Replies: 1
    Last Post: November 9th 2009, 08:28 PM
  5. Finding the area of a curve
    Posted in the Calculus Forum
    Replies: 1
    Last Post: May 3rd 2008, 06:17 AM

Search Tags


/mathhelpforum @mathhelpforum