Descriptive Statistics (mode, median, mean, range, standard deviation)

Question

1) 64.5  63.5  63.5  65  66  65.5  61  66  64  65

The data above represents the heights, in inches, of a random sample of adult American women. For this data calculate the:
(a) Mode
(b) Median
(c) Mean
(d) Range
(e) Standard Deviation

If any score beyond 2 standard deviations from the mean is considered unusual,

(f) What is the borderline value for unusually high for this data set?

[According to the Center for Health Statistics (1999-2002
study) the mean height of an American woman is 5’ 3.8”]

Answer 1

   First, add numbers:

   ___________________

          61.0

          63.5

          63.5

          64.0

          64.5

          65.0

          65.0

          65.5

          66.0

          66.0

    ___________

  Total: 644.0

 ____________

   n=10               

 

 

Mean=64.4

To find Median: 4 from top =64.5

                        4 from bottom= 65.0

                         Add                  ______

                                                 129.5

                         Divide by 2       ________

                                                     2

 

                           Median=      64.75

 

Mode ( Number that appears most often)= (65  and 66)

Range( Largest number minus smallest number)  66-61 = 5

Std Diev = (Range divided by 4)   =  5/4   =1.25

Two Sdiev =2x1.25 =2.50

 

                                                          61.90.............64.4.............66.90

                                                         -2 Sdiev           Mean             +2Sdiev