00:01
So in this problem, we're going to roll two dice, and we're interested in looking at the sum of those two dice.
00:04
More specifically, we want to find the probability that our sum is greater than nine or our sum is less than six.
00:13
The first thing to notice is that these two events are actually mutually exclusive.
00:17
And the reason why is because we cannot have a sum that is both greater than nine or less than six.
00:22
Because if the sum is greater than nine, then it can't be less than six.
00:25
So these two events are mutually exclusive, and that means we can simply write this probability, as the probability we get a sum greater than nine, plus the probability we get a sum less than six.
00:36
So let's work with this first one.
00:39
Let's look at how many different ways we can get a dice, a sum of our two dice to be greater than nine.
00:44
Well, we can get a four and a six, a six and a four.
00:48
We can get a four and a five, a five and a four.
00:51
We can also get a five and a five or a six and a six...