Question

Σ(x - x_bar) = 0 Please write out the equation in words as if you were reading it to someone and demonstrate how to use it with the following set of values: 48, 53, 74, 82, 99.

Answer 1

The equation:

:

means that the algebraic sum of deviation of each data point from the mean equals 0.

Demonstration:

Given set of values:

48, 53, 74, 82, 99

Mean () is calculated as follows:

From the given data, the following Table is calculated:

x	(x - )
48	48-71.2=- 23.2
53	53-71.2= - 18.2
74	74 - 71.2 = 2.8
82	82 - 71.2 = 10.8
99	99 - 71.2 = 27.8
Total =	0

This illustrates:

:

The algebraic sum of deviation of each data point from the mean equals 0.