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I'm in the process of finding $E(XY)$ where X and Y are non-independent Bernoulli random variables with both of them with probability of $\frac{n}{N}$

I understand that $E(XY)=\Sigma\Sigma x_{i}y_{i}P(X,Y)$ and this got me to the point where I can write: $E(XY)=P(X=1,Y=1)\cdot1+P(X=1,Y=0)\cdot0+P(X=0,Y=1)\cdot0+P(X=0,Y=0)\cdot0$ $=P(X=1,Y=1)$

But Im very lost here. Some help would be appreciated.

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    $X$ and $Y$ are both Bernoulli random variable with same probability of success. So $P(X=1)=P(Y=1)=p$ Nothing much is given to be honest. – 2017-02-16
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    You have correctly identified $\mathsf E(XY)=\mathsf P(X=1,Y=1)$. We *cannot* proceed because we do not know what this joint probability may be. Your post has specified that the variables are *not* independent yet *not* indicated what dependency they do have. – 2017-02-16

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