If necessary consult a list of formulas Ex VarX Value of 0 0
(If necessary, consult a list of formulas.)
E(x)=
Var(X)=
| Value | |
| 0 | 0.05 | 
| 10 | 0.05 | 
| 20 | 0.75 | 
| 30 | 0.05 | 
| 40 | 0.05 | 
| 50 | 0.05 | 
Solution
Consider this table:
x   P(x)   xP(x)   x^2 P(x)
 0   0.05   0   0
 10   0.05   0.5   5
 20   0.75   15   300
 30   0.05   1.5   45
 40   0.05   2   80
 50   0.05   2.5   125
 Total       21.5   555
 Thus,
E(x) = 21.5 [ANSWER]
var(x) = E(x^2) - E(x)^2 = 555 - 21.5^2 = 92.75 [answer]

