Question

Suppose that the overall probability of living to age 70 is 0.62 and that the overall probability of living to age 80 is 0.23. If a person reaches their 70th birthday, what is the probability that they will live to age 80?

Answer 1

Given :

P( X = 70 ) = 0.62 .

P( X = 80 ) = 0.23 .

To Find :

We need to find If a person reaches their 70th birthday, what is the probability that they will live to age 80 .

Solution :

We need to find :

`P(X=70 | X=80 )`

We know ,

`P(x,y ) = (P(x))/(P(y))`

So ,

`P(X=70 | X=80 )=(P(X=80))/(P(X=70))\\\\=(0.62)/(0.23)=0.371`

Hence , this is the required solution .