Question

Determine if the distribution represents a probability distribution. Then find Mean, Variance, and Standard Deviation. X 6 8 10 12 14 P(x) .25 .10 .30 .10 .25

Answer 1

Solution:

x	P(x)	x * P(x)	x2 * P(x)
6	0.25	1.5	9
8	0.1	0.8	6.4
10	0.3	3	30
12	0.1	1.2	14.4
14	0.25	3.5	49
Sum	1	10	108.8

Mean = X * P(X)

= 10

Standard deviation =

= X 2 * P(X) - 2

= 108.8 - (10)2 = 8.8

Standard deviation = = 2.9665