I have $n$ dots in a circle and $n$ edges that connect these dots.
Each dot is painted red or blue in a probability of $0.5$ each.
An edge is blue/red if both the dots it connects are blue/red.
Let $N$ be the number of red edges, find $E(N)$.
Can anyone give me a hint as to how to approach this? I thought about binomial probability for $N$ with $n$ and $0.5^2$ but the chances for success if the $2$ edges share a dot is $0.5^3$ not $0.5^4$ so thats not going to work.
Again I would like a hint not a solution.
Thanks!