Answer:
1060 ; 96400 ; 310.48
Explanation:
Given that:
P(X): __0.50 ___0.20 ____ 0.20 ____ 0.10
X : ___800 ___ 1200 ____ 1600 ____ 1000
The expected sales (m) : Σ(p * p(x))
(0.50 * 800) + (0.20 * 1200) + (0.20 * 1600) + ( 0.10 * 1000) = 1060
B.) variance (Var X) :
Σx²p - m²
(800^2*0.50) + (1200^2 * 0.20) + (1600^2 * 0.20) + (1000^2 * 0.10)] - m²
1220000 - 1060^2
= 96,400
Standard deviation = √variance
= √96400
= 310.48