Answer:
Given,
Mean = E(X) = 100
Variance = V(X) = 15
a)
E(X^2) = V(X) + [E(X)]^2
substitute values
= 15 + 100^2
= 10015
b)
E(3X+10) = 3*E(X) + 10
= 3*100 + 10
= 310
c)
E(-X) = - E(X)
= - 100
d)
V(-X) = (-1)^2*V(X)
= (-1)^2 *15
= 15
e)
D(-X) = sqrt(V(-X))
= sqrt(15)
= 3.873
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