00:01
In this problem it is said that a six -sided die is tossed five times.
00:05
We need to find the average number of fours and the variance of the number of fours.
00:09
So note that this situation represents a binomial distribution.
00:14
And what are the parameters for this distribution? they are n and p.
00:19
N is the number of trials, that will be five because the die is tossed five times.
00:24
And what is p? p is the probability of success.
00:27
Now we want to find the average number of fours, the variance of the number of fours.
00:31
So a success will be getting a four on tossing a die.
00:34
So the probability of success will be the probability of getting a four.
00:38
So this is the number of favorable outcomes divided by the total number of outcomes.
00:42
The total number of outcomes is six because we have a six -sided die.
00:45
And only one of those sides has a four on it, so the number of favorable outcomes is one...