00:01
The definition of conditional probability, the probability of b given a, is the probability of a and b over the probability of a.
00:10
And now when we're rolling two dice, our sums would be 2, 3, 4, 5, 6, 7, 7, 3, 4, 6, 7, 8, 4, 6, 7, 8, 9, 5, 6, 8, 9, 10, 6, 6, 8, 9, 10, 6, 6, 8, 8, 8, 10, 6, 6, 6, 8, 8, 8, 10, 6, 6, 6, 8, 8, 7, 7, 7, 8, 8, 8, 7, 8, 7, 6, 7, 7, 7, 7.
00:39
8, 9, 10, 11, and 7, 8, 9, 10, 11, 12.
00:47
So the sum of two dice is 6.
00:50
The only way that this can be, that at least one of the dice is a 3, is if both dice were a 3...