answer to this will be 1/2. the quesn was that given he has a ladies first policy, what is P(Second letter delivered to a female):If he delivers to ladies first then there will be 2 cases: FM, FF. So the given probability is 1/2
As far as i remember...the question was...IF there is a letter from a female, then we will consider that first...but there is a posibility dat both d leters r from males...m just telling what I thought...maybe m wrong... :( :(
If MM is the case then how do you give the second letter to a female? MF can't be a case. A second letter can be given to a female only when the first letter is also given to a female. which means that the cases would only be FM and FF.
there are 4 possibilities for your two letters: MM, MF, FM and FF. However, since the mailman delivers a female one first no matter what, the only three possibilities are actually MF, FM and FF. Of these, the other letter is from a male in 2 out of the three cases. Thus the answer is 1/3.