Computers x Households Px 0 300 1 400 2 200 3 100 aFind the

Computers (x)

Households

P(x)

0

300

1

400

2

200

3

100

a)Find the mean =

b) find the variance =

c) find the standard deviation==

Computers (x)	Households	P(x)
0	300
1	400
2	200
3	100

a)Find the mean Computers (x)HouseholdsP(x)0300 & b) find the variance = Computers (x)HouseholdsP(x)0300 & c) find the standard deviation== Computers (x)HouseholdsP(x)0300 &

Solution

a)Mean = [(0*300)+(1*400)+(2*200)+(3*100)]/(1+2+3)

             = 1100/6 = 183.33

b)Variance = [(0*{300-183.33}^2)+(1*{400-183.33}^2)+(2*{200-183.33}^2)+(3*{100-183.33}^2)]/(1+2+3)

                 = 11388.88

c)S.D = square root(11388.88)

         = 106.71