00:01
We are asked to find the probability that someone has an accident in the second year, given that he or she has had no accident in the first year.
00:12
And this is from example 3 -1.
00:16
So let's first define some events.
00:19
Let a be a person is accident -prone.
00:26
Let a -1 be that a person has accident in the first.
00:31
Year and a should be that a person has an accident in the second year.
00:38
And in the probabilities from example 3a, now probability of a be equal to 0 .3, which implies that probability of not a, that is a complement, will be 0 .7.
00:55
And probability of ai given a is equal to 0 .5 .2.
01:04
And probability of a .i, which implies that probability of not getting an accident, given that the person is accident prone, is 0 .6.
01:18
And again, probability that the person has an accident, given that the person is not accident prone is 0 .2, which implies that the probability of someone not getting an accident and given that the person is accident, not accident prone, is 0 .8.
01:47
So we have to make an important assumption that a random experiment that accident happens in some two different years are independent, given that a or, even that the person is accident prone or not accident prone, they are independent...