If you roll a 6-sided die 6 times, what is the best prediction possible for the number of times you will roll a five?

The best prediction possible for the number of times you will roll a five when rolling a 6-sided die 6 times would be 1 time. This is because each roll of the die is independent of the others, and the probability of rolling a five on any given roll is 1/6. Therefore, on average, you would expect to roll a five once in 6 rolls.