[tessarji]

I'm not DS, but...

This problem is meaningless without bounds. For example, imagine you're reached the N-1 number, and the value you recieve is 10. There are infinite real numbers less than this, and infinite real numbers larger. Therefore you have an undefined EV.

If you place a lower bound and upper bound on the real numbers this problem is solvable by working backwards from the N-1 case.

So I'd answer,

No, in the unbounded case.
Not really. Only factor is how close you are to N.
Yes.