if you roll a 6-sided fair dice three times, what's the probability of rolling a 1 at least once?
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zagle 8 months ago91 in 216 -
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Quickest way I can think of:
Probability of avoiding rolling a 1 in one roll - 5/6
Probability of avoiding rolling a 1 in three rolls - (5/6)^3
Probability of failing to avoid rolling a 1 in three rolls, i.e. probability of rolling a 1 at least once in three rolls - 1-(5/6)^3 = 91/216
And if that isn't enough, here's a python one-liner that counts all possible rolls of three dice to see how many contain at least one 1:print(len([i for i in itertools.product((1, 2, 3, 4, 5, 6), repeat=3) if 1 in i])) -
