Question

Determine the sample variance and standard deviation for this small dataset:

5
6
8

Include 2 decimal places in your answer (i.e, 4.35)

Answer 1

x	(x-x̅ )	(x - x̅)²
5	-1.33333	1.777778
6	-0.33333	0.111111
8	1.666667	2.777778
19		4.666667

Mean = ∑x/n         =19/3     =6.3333333

Sample standard deviation = √(∑(x - x̅)²/n-1)     =√(4.666667/3-1)     =1.527525     =1.53

Sample variance = ∑(x - x̅)²/n-1       =4.666667/3-1       =2.333333     =2.33