E(X) =ΣxP(x) =-1*2/3+2*1/3 =0
E(X2) =Σx2P(x) =-1^2*2/3+2^2*1/3 =2
Var(X) =E(X2)-(E(x))2 =2
similarly :
E(Y) =0.50
Var(Y) =6.25
a)
E(X+Y )=E(X)+E(Y) =0+0.5 =0.5
b)
var(X+Y)=Var(X)+Var(Y)=2+6.25 =8.25
Random variables X and Y have following distributions: PIX = -1) = 2/3, PIX = 2)...
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Practice problems using various statistical methods
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