SOLUTION: x P(X=x) 0 0.4 5 ? 10 0.3 fill in the missing number calculate mean and variance

Algebra ->  Distributive-associative-commutative-properties -> SOLUTION: x P(X=x) 0 0.4 5 ? 10 0.3 fill in the missing number calculate mean and variance       Log On


   

Question 1096929: x P(X=x)
0 0.4
5 ?
10 0.3
fill in the missing number
calculate mean and variance

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
The sum of probabilities must be 1.
0.4%2BP%285%29%2B0.3=1
P%285%29=0.3
.
.
mu=0%280.4%29%2B5%280.3%29%2B10%280.3%29=1.5%2B3=4.5
.
.
V=0%280-4.5%29%5E2%2B%280.3%29%285-4.5%29%5E2%2B%280.3%29%2810-4.5%29%5E2=50.75
sigma=sqrt%28V%29=sqrt%2850.75%29=7.12