In a dice with an odd number of sides, it is possible to get the expected value to show up in the die.
Proof:
The sum of all n numbers is n(n+1)/2, proof left to the reader.
If we divide it by n, we get (n+1)/2. Now (n+1)/2 is an integer when n+1 is even, so n must be odd.
Q.E.D ( also first time incorporating a mathematical proof on imgFlip, should I do more)