A statistic problem!


New member
Jan 22, 2017
Hello! I have an exam and i would appreciate if you could help me with a statistic problem since I had this problem in an old work and I didn't solved it

Here is the problem

A joint probability function of two random variables is :

P(Y=y/|X=x)=f(y,x)= (n!/(k!)*(n-k)!) * x(^y) *(1-x)^(n-y) when y=0,1,...n

fx(x)=1 when 0<=x<=1 and fx(X)=0 in other space. FIND E(Y)

Please if you could help me i would appreciate a lot because i have a such a difficult exam and i would like to have the answer of ths problem :)