00:01
Now in this problem, we want to find the probability at least one of the fallups occurs.
00:04
And so we want the probability of a or b or c.
00:12
Now, if we group this like so, using our famous property from probability, this is equal to the probability of a, plus the probability of b or c, minus the probability of a and b or c.
00:34
Now from here, we will still have the probability of a, plus we're going to make use of that same property here for b or c.
00:43
And so this is the probability of b plus the probability of c.
00:49
Now that would be minus the probability of both of them, but we're told that it is mutually exclusive.
00:54
And so we don't have to make use of that here because that's just zero.
01:00
And then minus making use of our distributive property...