题目内容:
Given P(X =2, Y= 10) =0.3, P(X=6, Y=2.5) =0.4, and P(X =10,Y=0)=0.3, then Cov(XY) is:()
A. -12.0.
B. 24.0.
C. 6.0.
参考答案:
Given P(X =2, Y= 10) =0.3, P(X=6, Y=2.5) =0.4, and P(X =10,Y=0)=0.3, then Cov(XY) is:()
A. -12.0.
B. 24.0.
C. 6.0.