00:01
The mean number of serious accidents per year is 5.
00:04
So i'm going to put that as lambda equals 5.
00:07
That's the rate at which this happens.
00:09
And we're going to be using the poisson distribution.
00:13
This applies if you have these random independent occurrences at a given average rate.
00:19
And that seems fair here.
00:20
We have the same number of employees.
00:21
We have the average number of accidents per year.
00:24
We can use a poisson distribution.
00:25
The formula is the probability of exactly x occurrences is lambda to the power of x, e to the minus lambda, over x factorial.
00:36
So for part a, probability of no accidents is the probability x equals 0.
00:42
So that would be 5 to the power of 0, that's just 1, over 0 factorial, that's just 1 as well.
00:49
So it's just e to the minus 5.
00:51
Which, let me put that into my calculator.
00:53
0 .0 .0 .6, 7.
01:02
Upby, 1 accident.
01:06
So the probability x equals 1.
01:09
So we have 5 to the power of 1...