00:01
This problem is talking about a binomial distribution.
00:04
Why is a binomial distribution? because we only have two outcomes.
00:08
Either the driver has an accident, which is a probability of 0 .2, or the driver doesn't have an accident, which is 1 minus 0 .2, a probability of 0 .8.
00:22
Then all we need to do is write the formula for binomial distribution.
00:27
Probability of x happening is equal to...
00:31
N combination x times p to the power of x times q to the power of n minus x we have all this information the only thing we're missing is n which is six because we have a total of six drivers and x is just whatever probability we're looking for so let's write one of these probabilities for example if we were to look for the probability of exactly two drivers having an accident, we would have to write the equation as n, which is six, combination.
01:09
X is two, because we're looking for the probability of exactly two drivers, times p, which is the probability of having an accident, which is 0 .2, raised to the power of x.
01:20
Right now we're calculating for two drivers, times q, which is the probability of not having an accident, raised to the power of 6, which is n minus 2, which is x.
01:33
We put this into the calculator, and we can get that the probability of two persons having an accident is 0 .24.
01:45
For example, if we want to find the probability of exactly 3 having an accident, we replace 2 for 3.
01:50
If you want to find the probability of exactly 4, we replace 4.
01:53
4.
01:54
So x is the probability of how many drivers having an accident.
01:59
With this information, we can build a table with all the possible combinations.
02:05
This table is a table made an xcel.
02:08
Here we have p and q, which are the same values all over the place...