Question

STATISTICS
http://i1084.photobucket.com/albums/j409/QRAWarrior/STAB22-IfQn.png
(I used A and B in place of D and N; really I meant to use D and N!)

Let D be event "flight is delayed"
Let N be event "luggage does not arrive"

Which conditional probability is relevant, given the following statement:
If the flight is delayed, the probability that the luggage will make it is only 0.65.

a) P(N|D)
or
b) P(D|N)

Answer 1

Attempt:
I said P(N|D) because I thought that what they say after the if is what we are given; in this case, the flguht is delayed. So, the statement after the , would be what goes before the vertical line.

However, the correct answer is actually P(D|N). Why?

Answer 2

@Zarkon