Final answer:
The probability of rolling a number at least once when a fair die is rolled six times is approximately 0.999978.
Step-by-step explanation:
The probability of rolling a number at least once when a fair die is rolled six times can be calculated by finding the complement of the event where the die does not come up at all. The probability of the complement is equal to 1 minus the probability of the event.
So, the probability of rolling a number at least once is 1 - (probability of not rolling any number) = 1 - (1/6)6 = 1 - 1/46656 ≈ 0.999978.