Answer:
91/216
Explanation:
The probability of getting a 4 in the first three rolls is 1 minus the probability of not getting a 4 on any of the rolls.
P(at least one 4) = 1 − P(no 4s)
P(at least one 4) = 1 − (5/6)³
P(at least one 4) = 91/216
Alternatively, you can calculate it this way.
The probability of getting a 4 on the first roll is 1/6.
The probability of getting a 4 on the second roll is (5/6) (1/6) = 5/36.
The probability of getting a 4 on the third roll is (5/6) (5/6) (1/6) = 25/216.
The probability of any of the three events is 1/6 + 5/36 + 25/216 = 91/216.