Originally Posted by

**0123** I would ask some more questions.Thanks a lot again.

So,

there are 10,000 people in total, it is the population.

there's a table

male female

smoker 15% 20%

not smoker 35% 30%

It says, knowing that a person is taken randomly from the population and that this person smokes, compute the probability that it is a woman.

The book says

P(F|S) proportional(I do not know how to write that kind of infinite symbol) to P(F) P(S|F) = 0.5 x 0.4

P(M|S) proportional to P(M) P(S|M)= 0.5x 0.3

why does it write o.4 and 0.3? should not it be respectively 0.20 and 0.15? thanks a lot for your help!