the probability on a normal six cube would be 25 percent. this is so because there are both 3 even and odd numbers on a six cube and there's a 50 percent chance (theoretically) each time. so if you were to roll it 2 times you would have 4 possibilities:
Even then Odd
Odd then Even
Odd then Odd
Even then Even
a 1 out of 4 chance is 25 percent so that's how you get 25 percent