The probability of not rolling a four would be 5/6, because there are 6 sides to the dice and '4' counts as only one side. A die being rolled five times, all of which are no fours, would be the following:

(5/6)^5

5/6 coming from the probably of rolling a non-four number one time, and 5 coming from the die being rolled a total of 5 times. Simplify it, and you will get:

3125/7776

Estimating this through a calculator, the answer will be roughly **0.40**