Results 1 to 4 of 4

Math Help - Calculating standard deviation.

  1. #1
    Junior Member allsmiles's Avatar
    Joined
    May 2010
    From
    Altlanta GA
    Posts
    53

    Calculating standard deviation.

    An example of the calculation for the population standard deviation of a set of data is shown. Approximate the population standard deviation for the set { 4 , 5 , 7 , 5 , 6 , 3}, to the nearest tenth.



    1.3 is it the Correct Answer
    ????????????.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor harish21's Avatar
    Joined
    Feb 2010
    From
    Dirty South
    Posts
    1,036
    Thanks
    10
    Quote Originally Posted by allsmiles View Post
    An example of the calculation for the population standard deviation of a set of data is shown. Approximate the population standard deviation for the set { 4 , 5 , 7 , 5 , 6 , 3}, to the nearest tenth.



    1.3 is it the Correct Answer
    ????????????.
    1.3 is correct
    Follow Math Help Forum on Facebook and Google+

  3. #3
    MHF Contributor
    Joined
    Dec 2009
    Posts
    3,120
    Thanks
    1
    Quote Originally Posted by allsmiles View Post
    An example of the calculation for the population standard deviation of a set of data is shown. Approximate the population standard deviation for the set { 4 , 5 , 7 , 5 , 6 , 3}, to the nearest tenth.



    1.3 is it the Correct Answer
    ????????????.
    Hi allsmiles,

    just follow the procedure as detailed.

    1. Calculate the mean of the six numbers.
    2. Calculate the deviations of the six numbers from the mean.
    3. Square all the deviations
    4. Sum all the squares of the deviations
    5. Find the average square by dividing by 6
    6. Take the square root

    \mu=\frac{4+5+7+5+6+3}{6}=\frac{30}{6}=5

    The deviations are 4-5, 5-5, 7-5, 5-5, 6-5, 3-5

    Hence, square these, find the average of the squares and take the square root.

    I get \sqrt{1.67}=1.2922, then just round it off, but go through the workings.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    A riddle wrapped in an enigma
    masters's Avatar
    Joined
    Jan 2008
    From
    Big Stone Gap, Virginia
    Posts
    2,551
    Thanks
    12
    Awards
    1
    Quote Originally Posted by allsmiles View Post
    An example of the calculation for the population standard deviation of a set of data is shown. Approximate the population standard deviation for the set { 4 , 5 , 7 , 5 , 6 , 3}, to the nearest tenth.



    1.3 is it the Correct Answer
    ????????????.
    Hi allsmiles,

    \mu=5

    From the table, you can conclude:

    \sigma=\sqrt{\frac{10}{6}}\approx 1.3


    Edit: ArchieMeade..what he said!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Calculating correct mean and standard deviation
    Posted in the Statistics Forum
    Replies: 3
    Last Post: August 17th 2010, 01:44 AM
  2. Calculating the standard deviation
    Posted in the Statistics Forum
    Replies: 4
    Last Post: December 9th 2009, 02:17 PM
  3. Replies: 7
    Last Post: July 29th 2009, 05:49 PM
  4. Replies: 5
    Last Post: May 18th 2009, 04:14 AM
  5. standard deviation and mean deviation
    Posted in the Statistics Forum
    Replies: 1
    Last Post: March 16th 2008, 05:09 AM

Search Tags


/mathhelpforum @mathhelpforum