General Statistics
Worksheet
Basic Statistics   
Mean and Variance 

 

Worksheet Tools - Mean and Sample Variance - To compute the sample mean and variance Example

Steps: (1) Fill out table first with Class Midpoint, X and frequency, f.  (2) Use formulas to calculate group statistics 
 
Sample
Index, i		 Sample Value
X
(1)		 Mean
(4)

 (3) divided by (2)		 Difference

(5) =

(1) - (4)

 Squares

(6)=

(5)2
1        
2        
3        
4        
5        
6        
7        
8        
9        
10        
11



12



Sum, sample 
size
n=______ (2)

n-1= _______ (8)

 (3)

 Same values
in each row		   Sum of Square 
(7)=

Total of (6)
 
Arithmetic mean

=

 Variance:

  = (7) divided by (8)
 
 

 Standard  deviation:   
 

=